#!/usr/bin/env python 
"""
Comments starting "#LT" or "#CLT" are by Chris Lusby Taylor who rewrote the engraving function in 2011.
History of CLT changes to engraving and other functions it uses:
9 May 2011 Changed test of tool diameter to square it
10 May Note that there are many unused functions, including:
	  bound_to_bound_distance, csp_curvature_radius_at_t,
        csp_special_points, csplength, rebuild_csp, csp_slope,
        csp_simple_bound_to_point_distance, csp_bound_to_point_distance,
        bez_at_t, bez_to_point_distance, bez_normalized_slope, matrix_mul, transpose
       Fixed csp_point_inside_bound() to work if x outside bounds
20 May Now encoding the bisectors of angles.
23 May Using r/cos(a) instead of normalised normals for bisectors of angles.
23 May Note that Z values generated for engraving are in pixels, not mm.
       Removed the biarc curves - straight lines are better.
24 May Changed Bezier slope calculation to be less sensitive to tiny differences in points.
       Added use of self.options.engraving_newton_iterations to control accuracy
25 May Big restructure and new recursive function.
	   Changed the way I treat corners - I now find if the centre of a proposed circle is
                within the area bounded by the line being tested and the two angle bisectors at
		    its ends. See get_radius_to_line().
29 May Eliminating redundant points. If A,B,C colinear, drop B
30 May Eliminating redundant lines in divided Beziers. Changed subdivision of lines
  7Jun Try to show engraving in 3D
 8 Jun Displaying in stereo 3D.
       Fixed a bug in bisect - it could go wrong due to rounding errors if
			1+x1.x2+y1.y2<0 which should never happen. BTW, I spotted a non-normalised normal
			returned by csp_normalized_normal. Need to check for that.
 9 Jun Corrected spelling of 'definition' but still match previous 'defention' and 	  'defenition' if found in file
	 Changed get_tool to find 1.6.04 tools or new tools with corrected spelling
10 Jun Put 3D into a separate layer called 3D, created unless it already exists
       Changed csp_normalized_slope to reject lines shorter than 1e-9.
10 Jun Changed all dimensions seen by user to be mm/inch, not pixels. This includes
	  tool diameter, maximum engraving distance, tool shape and all Z values.
12 Jun ver 208 Now scales correctly if orientation points moved or stretched.
12 Jun ver 209. Now detect if engraving toolshape not a function of radius
                Graphics now indicate Gcode toolpath, limited by min(tool diameter/2,max-dist)
TODO Change line division to be recursive, depending on what line is touched. See line_divide


engraving() functions (c) 2011 Chris Lusby Taylor, clusbytaylor@enterprise.net
Copyright (C) 2009 Nick Drobchenko, nick@cnc-club.ru
based on gcode.py (C) 2007 hugomatic... 
based on addnodes.py (C) 2005,2007 Aaron Spike, aaron@ekips.org
based on dots.py (C) 2005 Aaron Spike, aaron@ekips.org
based on interp.py (C) 2005 Aaron Spike, aaron@ekips.org
based on bezmisc.py (C) 2005 Aaron Spike, aaron@ekips.org
based on cubicsuperpath.py (C) 2005 Aaron Spike, aaron@ekips.org

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
"""

###
###		Gcodetools v 1.7
###

gcodetools_current_version = "1.7"

import inkex, simplestyle, simplepath
import cubicsuperpath, simpletransform, bezmisc

import os
import math
import bezmisc
import re
import copy
import sys
import time
import cmath
import numpy
import codecs
import random
import gettext
_ = gettext.gettext

 
### Check if inkex has errormsg (0.46 version does not have one.) Could be removed later.
if "errormsg" not in dir(inkex):
	inkex.errormsg = lambda msg: sys.stderr.write((unicode(msg) + "\n").encode("UTF-8"))


def bezierslopeatt(((bx0,by0),(bx1,by1),(bx2,by2),(bx3,by3)),t):
	ax,ay,bx,by,cx,cy,x0,y0=bezmisc.bezierparameterize(((bx0,by0),(bx1,by1),(bx2,by2),(bx3,by3)))
	dx=3*ax*(t**2)+2*bx*t+cx
	dy=3*ay*(t**2)+2*by*t+cy
	if dx==dy==0 : 
		dx = 6*ax*t+2*bx
		dy = 6*ay*t+2*by
		if dx==dy==0 : 
			dx = 6*ax
			dy = 6*ay
			if dx==dy==0 : 
				print_("Slope error x = %s*t^3+%s*t^2+%s*t+%s, y = %s*t^3+%s*t^2+%s*t+%s,  t = %s, dx==dy==0" % (ax,bx,cx,dx,ay,by,cy,dy,t))
				print_(((bx0,by0),(bx1,by1),(bx2,by2),(bx3,by3)))
				dx, dy = 1, 1
				
	return dx,dy
bezmisc.bezierslopeatt = bezierslopeatt


def ireplace(self,old,new,count=0):
	pattern = re.compile(re.escape(old),re.I)
	return re.sub(pattern,new,self,count) 

def isset(variable):
	# VARIABLE NAME SHOULD BE A STRING! Like isset("foobar")
	return variable in locals() or variable in globals()
	
	
################################################################################
###
###		Styles and additional parameters
###
################################################################################

math.pi2 = math.pi*2
straight_tolerance = 0.0001
straight_distance_tolerance = 0.0001
engraving_tolerance = 0.0001
loft_lengths_tolerance = 0.0000001

EMC_TOLERANCE_EQUAL = 0.00001

options = {}
defaults = {
'header': """%
(Header)
(Generated by gcodetools from Inkscape.)
(Using default header. To add your own header create file "header" in the output dir.)
M3
(Header end.)
""",
'footer': """
(Footer)
M5
G00 X0.0000 Y0.0000
M2
(Using default footer. To add your own footer create file "footer" in the output dir.)
(end)
%"""
}

intersection_recursion_depth = 10
intersection_tolerance = 0.00001

styles = {
		"in_out_path_style" : simplestyle.formatStyle({ 'stroke': '#0072a7', 'fill': 'none', 'stroke-width':'1', 'marker-mid':'url(#InOutPathMarker)' }),
		
		"loft_style" : {
				'main curve':	simplestyle.formatStyle({ 'stroke': '#88f', 'fill': 'none', 'stroke-width':'1', 'marker-end':'url(#Arrow2Mend)' }),
			},
		"biarc_style" : {
				'biarc0':	simplestyle.formatStyle({ 'stroke': '#88f', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'1' }),
				'biarc1':	simplestyle.formatStyle({ 'stroke': '#8f8', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'1' }),
				'line':		simplestyle.formatStyle({ 'stroke': '#f88', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'1' }),
				'area':		simplestyle.formatStyle({ 'stroke': '#777', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'0.1' }),
			},
		"biarc_style_dark" : {
				'biarc0':	simplestyle.formatStyle({ 'stroke': '#33a', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'1' }),
				'biarc1':	simplestyle.formatStyle({ 'stroke': '#3a3', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'1' }),
				'line':		simplestyle.formatStyle({ 'stroke': '#a33', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'1' }),
				'area':		simplestyle.formatStyle({ 'stroke': '#222', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'0.3' }),
			},
		"biarc_style_dark_area" : {
				'biarc0':	simplestyle.formatStyle({ 'stroke': '#33a', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'0.1' }),
				'biarc1':	simplestyle.formatStyle({ 'stroke': '#3a3', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'0.1' }),
				'line':		simplestyle.formatStyle({ 'stroke': '#a33', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'0.1' }),
				'area':		simplestyle.formatStyle({ 'stroke': '#222', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'0.3' }),
			},
		"biarc_style_i"  : {
				'biarc0':	simplestyle.formatStyle({ 'stroke': '#880', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'1' }),
				'biarc1':	simplestyle.formatStyle({ 'stroke': '#808', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'1' }),
				'line':		simplestyle.formatStyle({ 'stroke': '#088', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'1' }),
				'area':		simplestyle.formatStyle({ 'stroke': '#999', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'0.3' }),
			},
		"biarc_style_dark_i" : {
				'biarc0':	simplestyle.formatStyle({ 'stroke': '#dd5', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'1' }),
				'biarc1':	simplestyle.formatStyle({ 'stroke': '#d5d', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'1' }),
				'line':		simplestyle.formatStyle({ 'stroke': '#5dd', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'1' }),
				'area':		simplestyle.formatStyle({ 'stroke': '#aaa', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'0.3' }),
			},
		"biarc_style_lathe_feed" : {
				'biarc0':	simplestyle.formatStyle({ 'stroke': '#07f', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'.4' }),
				'biarc1':	simplestyle.formatStyle({ 'stroke': '#0f7', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'.4' }),
				'line':		simplestyle.formatStyle({ 'stroke': '#f44', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'.4' }),
				'area':		simplestyle.formatStyle({ 'stroke': '#aaa', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'0.3' }),
			},
		"biarc_style_lathe_passing feed" : {
				'biarc0':	simplestyle.formatStyle({ 'stroke': '#07f', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'.4' }),
				'biarc1':	simplestyle.formatStyle({ 'stroke': '#0f7', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'.4' }),
				'line':		simplestyle.formatStyle({ 'stroke': '#f44', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'.4' }),
				'area':		simplestyle.formatStyle({ 'stroke': '#aaa', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'0.3' }),
			},
		"biarc_style_lathe_fine feed" : {
				'biarc0':	simplestyle.formatStyle({ 'stroke': '#7f0', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'.4' }),
				'biarc1':	simplestyle.formatStyle({ 'stroke': '#f70', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'.4' }),
				'line':		simplestyle.formatStyle({ 'stroke': '#744', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'.4' }),
				'area':		simplestyle.formatStyle({ 'stroke': '#aaa', 'fill': 'none', "marker-end":"url(#DrawCurveMarker)", 'stroke-width':'0.3' }),
			},
		"area artefact": 		simplestyle.formatStyle({ 'stroke': '#ff0000', 'fill': '#ffff00', 'stroke-width':'1' }),
		"area artefact arrow":	simplestyle.formatStyle({ 'stroke': '#ff0000', 'fill': '#ffff00', 'stroke-width':'1' }),
		"dxf_points":		 	simplestyle.formatStyle({ "stroke": "#ff0000", "fill": "#ff0000"}),
		
	}



################################################################################
###		Gcode additional functions
################################################################################

def gcode_comment_str(s, replace_new_line = False):
	if replace_new_line :
		s = re.sub(r"[\n\r]+", ".", s)
	res = ""
	if s[-1] == "\n" : s = s[:-1]
	for a in s.split("\n") :
		if a != "" : 
			res +=  "(" + re.sub(r"[\(\)\\\n\r]", ".", a) + ")\n"
		else : 	
			res +=  "\n"
	return res
	
def gcode_comments(s):
	res = ""
	res = s.replace('(',';')
	res = res.replace(')','')
	res = res.replace('%','')
	return res


################################################################################
###		Cubic Super Path additional functions
################################################################################


def csp_from_polyline(line) :
	return [ [ [point[:] for k in range(3) ] for point in subline ]  for subline in line ]
	
def csp_remove_zerro_segments(csp, tolerance = 1e-7):	
	res = []
	for subpath in csp:
		if len(subpath) > 0 :
			res.append([subpath[0]])
			for sp1,sp2 in zip(subpath,subpath[1:]) :
				if point_to_point_d2(sp1[1],sp2[1])<=tolerance and point_to_point_d2(sp1[2],sp2[1])<=tolerance and point_to_point_d2(sp1[1],sp2[0])<=tolerance :
					res[-1][-1][2] = sp2[2]
				else :
					res[-1].append(sp2)
	return res
			

	


def point_inside_csp(p,csp, on_the_path = True) :
	# we'll do the raytracing and see how many intersections are there on the ray's way. 
	# if number of intersections is even then point is outside.
	# ray will be x=p.x and y=>p.y
	# you can assing any value to on_the_path, by dfault if point is on the path 
	# function will return thai it's inside the path. 
	x,y = p
	ray_intersections_count = 0
	for subpath in csp :
		
		for i in range(1, len(subpath)) :
			sp1, sp2 = subpath[i-1], subpath[i]
			ax,ay,bx,by,cx,cy,dx,dy = csp_parameterize(sp1,sp2)
		 	if  ax==0 and bx==0 and cx==0 and dx==x : 
		 		#we've got a special case here
		 		b = csp_true_bounds( [[sp1,sp2]])
		 		if  b[1][1]<=y<=b[3][1] :
		 			# points is on the path 
			 		return on_the_path
			 	else :
			 		# we can skip this segment because it wont influence the answer.
			 		pass	
		 	else: 
	 			for t in csp_line_intersection([x,y],[x,y+5],sp1,sp2) :
	 				if t == 0 or t == 1 :
	 					#we've got another special case here
		 				x1,y1 = csp_at_t(sp1,sp2,t)
		 				if y1==y : 
		 					# the point is on the path 
		 					return on_the_path
	 					# if t == 0 we sould have considered this case previously. 
	 					if t == 1 :
							# we have to check the next segmant if it is on the same side of the ray
							st_d = csp_normalized_slope(sp1,sp2,1)[0]
							if st_d == 0 : st_d = csp_normalized_slope(sp1,sp2,0.99)[0]
							
							for j in range(1, len(subpath)+1):
								if (i+j) % len(subpath) == 0  : continue # skip the closing segment 
								sp11,sp22 = subpath[(i-1+j) % len(subpath)], subpath[(i+j) % len(subpath)]
								ax1,ay1,bx1,by1,cx1,cy1,dx1,dy1 = csp_parameterize(sp1,sp2)
		 						if  ax1==0 and bx1==0 and cx1==0 and dx1==x : continue # this segment parallel to the ray, so skip it 
								en_d = csp_normalized_slope(sp11,sp22,0)[0]
								if en_d == 0 : en_d = csp_normalized_slope(sp11,sp22,0.01)[0]
								if st_d*en_d <=0 : 
			 						ray_intersections_count += 1
			 						break 
	 				else :	
		 				x1,y1 = csp_at_t(sp1,sp2,t)
		 				if y1==y : 
		 					# the point is on the path 
		 					return on_the_path
		 				else :
		 					if y1>y and 3*ax*t**2 + 2*bx*t + cx !=0 : # if it's 0 the path only touches the ray
		 						ray_intersections_count += 1 	
	return ray_intersections_count%2 == 1 				

def csp_close_all_subpaths(csp, tolerance = 0.000001):
	for i in range(len(csp)):
		if point_to_point_d2(csp[i][0][1] , csp[i][-1][1])> tolerance**2 :
			csp[i][-1][2] = csp[i][-1][1][:] 
			csp[i] += [ [csp[i][0][1][:] for j in range(3)] ]
		else: 
			if csp[i][0][1] != csp[i][-1][1] : 
				csp[i][-1][1] = csp[i][0][1][:]
	return csp

def csp_simple_bound(csp):
	minx,miny,maxx,maxy = None,None,None,None
	for subpath in csp:
		for sp in subpath : 
			for p in sp:
				minx = min(minx,p[0]) if minx!=None else p[0]
				miny = min(miny,p[1]) if miny!=None else p[1]
				maxx = max(maxx,p[0]) if maxx!=None else p[0]
				maxy = max(maxy,p[1]) if maxy!=None else p[1]
	return minx,miny,maxx,maxy		


def csp_segment_to_bez(sp1,sp2) :
	return sp1[1:]+sp2[:2]


def bound_to_bound_distance(sp1,sp2,sp3,sp4) :
	min_dist = 1e100
	max_dist = 0
	points1 = csp_segment_to_bez(sp1,sp2)
	points2 = csp_segment_to_bez(sp3,sp4)
	for i in range(4) :
		for j in range(4) :
			min_, max_ = line_to_line_min_max_distance_2(points1[i-1], points1[i], points2[j-1], points2[j])
			min_dist = min(min_dist,min_)
			max_dist = max(max_dist,max_)
			print_("bound_to_bound", min_dist, max_dist)
	return min_dist, max_dist
	
def csp_to_point_distance(csp, p, dist_bounds = [0,1e100], tolerance=.01) :
	min_dist = [1e100,0,0,0]
	for j in range(len(csp)) :
		for i in range(1,len(csp[j])) :
			d = csp_seg_to_point_distance(csp[j][i-1],csp[j][i],p,sample_points = 5, tolerance = .01)
			if d[0] < dist_bounds[0] : 
#				draw_pointer( list(csp_at_t(subpath[dist[2]-1],subpath[dist[2]],dist[3]))
#					+list(csp_at_t(csp[dist[4]][dist[5]-1],csp[dist[4]][dist[5]],dist[6])),"red","line", comment = math.sqrt(dist[0]))
				return [d[0],j,i,d[1]]
			else : 
				if d[0] < min_dist[0] : min_dist = [d[0],j,i,d[1]]
	return min_dist
			
def csp_seg_to_point_distance(sp1,sp2,p,sample_points = 5, tolerance = .01) :
	ax,ay,bx,by,cx,cy,dx,dy = csp_parameterize(sp1,sp2)
	dx, dy = dx-p[0], dy-p[1]
	if sample_points < 2 : sample_points = 2
	d = min( [(p[0]-sp1[1][0])**2 + (p[1]-sp1[1][1])**2,0.], [(p[0]-sp2[1][0])**2 + (p[1]-sp2[1][1])**2,1.]	)	
	for k in range(sample_points) :
		t = float(k)/(sample_points-1)
		i = 0
		while i==0 or abs(f)>0.000001 and i<20 : 
			t2,t3 = t**2,t**3
			f = (ax*t3+bx*t2+cx*t+dx)*(3*ax*t2+2*bx*t+cx) + (ay*t3+by*t2+cy*t+dy)*(3*ay*t2+2*by*t+cy)
			df = (6*ax*t+2*bx)*(ax*t3+bx*t2+cx*t+dx) + (3*ax*t2+2*bx*t+cx)**2 + (6*ay*t+2*by)*(ay*t3+by*t2+cy*t+dy) + (3*ay*t2+2*by*t+cy)**2
			if df!=0 :
				t = t - f/df
			else :	
				break
			i += 1	
		if 0<=t<=1 : 
			p1 = csp_at_t(sp1,sp2,t)
			d1 = (p1[0]-p[0])**2 + (p1[1]-p[1])**2
			if d1 < d[0] :
				d = [d1,t]
	return d	


def csp_seg_to_csp_seg_distance(sp1,sp2,sp3,sp4, dist_bounds = [0,1e100], sample_points = 5, tolerance=.01) : 
	# check the ending points first
	dist =	csp_seg_to_point_distance(sp1,sp2,sp3[1],sample_points, tolerance)
	dist += [0.]
	if dist[0] <= dist_bounds[0] : return dist
	d = csp_seg_to_point_distance(sp1,sp2,sp4[1],sample_points, tolerance)
	if d[0]<dist[0] :
		dist = d+[1.]
		if dist[0] <= dist_bounds[0] : return dist
	d =	csp_seg_to_point_distance(sp3,sp4,sp1[1],sample_points, tolerance)
	if d[0]<dist[0] :
		dist = [d[0],0.,d[1]]
		if dist[0] <= dist_bounds[0] : return dist
	d =	csp_seg_to_point_distance(sp3,sp4,sp2[1],sample_points, tolerance)
	if d[0]<dist[0] :
		dist = [d[0],1.,d[1]]
		if dist[0] <= dist_bounds[0] : return dist
	sample_points -= 2
	if sample_points < 1 : sample_points = 1
	ax1,ay1,bx1,by1,cx1,cy1,dx1,dy1 = csp_parameterize(sp1,sp2)
	ax2,ay2,bx2,by2,cx2,cy2,dx2,dy2 = csp_parameterize(sp3,sp4)
	#	try to find closes points using Newtons method
	for k in range(sample_points) :
		for j in range(sample_points) : 
			t1,t2 = float(k+1)/(sample_points+1), float(j)/(sample_points+1)
			t12, t13, t22, t23 = t1*t1, t1*t1*t1, t2*t2, t2*t2*t2
			i = 0
			F1, F2, F = [0,0], [[0,0],[0,0]], 1e100
			x,y   = ax1*t13+bx1*t12+cx1*t1+dx1 - (ax2*t23+bx2*t22+cx2*t2+dx2), ay1*t13+by1*t12+cy1*t1+dy1 - (ay2*t23+by2*t22+cy2*t2+dy2)			
			while i<2 or abs(F-Flast)>tolerance and i<30 :
				#draw_pointer(csp_at_t(sp1,sp2,t1))
				f1x = 3*ax1*t12+2*bx1*t1+cx1
				f1y = 3*ay1*t12+2*by1*t1+cy1
				f2x = 3*ax2*t22+2*bx2*t2+cx2
				f2y = 3*ay2*t22+2*by2*t2+cy2
				F1[0] = 2*f1x*x +  2*f1y*y
				F1[1] = -2*f2x*x -  2*f2y*y
				F2[0][0] =  2*(6*ax1*t1+2*bx1)*x + 2*f1x*f1x + 2*(6*ay1*t1+2*by1)*y +2*f1y*f1y
				F2[0][1] = -2*f1x*f2x - 2*f1y*f2y
				F2[1][0] = -2*f2x*f1x - 2*f2y*f1y 
				F2[1][1] = -2*(6*ax2*t2+2*bx2)*x + 2*f2x*f2x - 2*(6*ay2*t2+2*by2)*y + 2*f2y*f2y
				F2 = inv_2x2(F2)
				if F2!=None :
					t1 -= ( F2[0][0]*F1[0] + F2[0][1]*F1[1] )
					t2 -= ( F2[1][0]*F1[0] + F2[1][1]*F1[1] )
					t12, t13, t22, t23 = t1*t1, t1*t1*t1, t2*t2, t2*t2*t2
					x,y   = ax1*t13+bx1*t12+cx1*t1+dx1 - (ax2*t23+bx2*t22+cx2*t2+dx2), ay1*t13+by1*t12+cy1*t1+dy1 - (ay2*t23+by2*t22+cy2*t2+dy2)
					Flast = F
					F = x*x+y*y
				else : 
					break
				i += 1
			if F < dist[0] and 0<=t1<=1 and 0<=t2<=1:
				dist = [F,t1,t2]
				if dist[0] <= dist_bounds[0] : 
					return dist
	return dist			


def csp_to_csp_distance(csp1,csp2, dist_bounds = [0,1e100], tolerance=.01) : 
	dist = [1e100,0,0,0,0,0,0]
	for i1 in range(len(csp1)) : 
		for j1 in range(1,len(csp1[i1])) :
			for i2 in range(len(csp2)) :
				for j2 in range(1,len(csp2[i2])) :
					d = csp_seg_bound_to_csp_seg_bound_max_min_distance(csp1[i1][j1-1],csp1[i1][j1],csp2[i2][j2-1],csp2[i2][j2])
					if d[0] >= dist_bounds[1] : continue
					if  d[1] < dist_bounds[0] : return [d[1],i1,j1,1,i2,j2,1]
					d = csp_seg_to_csp_seg_distance(csp1[i1][j1-1],csp1[i1][j1],csp2[i2][j2-1],csp2[i2][j2], dist_bounds, tolerance=tolerance)
					if d[0] < dist[0] :
						dist = [d[0], i1,j1,d[1], i2,j2,d[2]]
					if dist[0] <= dist_bounds[0] :	
						return dist
			if dist[0] >= dist_bounds[1] :	
				return dist
	return dist
#	draw_pointer( list(csp_at_t(csp1[dist[1]][dist[2]-1],csp1[dist[1]][dist[2]],dist[3]))
#				+ list(csp_at_t(csp2[dist[4]][dist[5]-1],csp2[dist[4]][dist[5]],dist[6])), "#507","line")
					
					
def csp_split(sp1,sp2,t=.5) :
	[x1,y1],[x2,y2],[x3,y3],[x4,y4] = sp1[1], sp1[2], sp2[0], sp2[1] 
	x12 = x1+(x2-x1)*t
	y12 = y1+(y2-y1)*t
	x23 = x2+(x3-x2)*t
	y23 = y2+(y3-y2)*t
	x34 = x3+(x4-x3)*t
	y34 = y3+(y4-y3)*t
	x1223 = x12+(x23-x12)*t
	y1223 = y12+(y23-y12)*t
	x2334 = x23+(x34-x23)*t
	y2334 = y23+(y34-y23)*t
	x = x1223+(x2334-x1223)*t
	y = y1223+(y2334-y1223)*t
	return [sp1[0],sp1[1],[x12,y12]], [[x1223,y1223],[x,y],[x2334,y2334]], [[x34,y34],sp2[1],sp2[2]]
	
	
def csp_true_bounds(csp) :
	# Finds minx,miny,maxx,maxy of the csp and return their (x,y,i,j,t) 
	minx = [float("inf"), 0, 0, 0]																																																																																																								
	maxx = [float("-inf"), 0, 0, 0]
	miny = [float("inf"), 0, 0, 0]
	maxy = [float("-inf"), 0, 0, 0]
	for i in range(len(csp)):
		for j in range(1,len(csp[i])):
			ax,ay,bx,by,cx,cy,x0,y0 = bezmisc.bezierparameterize((csp[i][j-1][1],csp[i][j-1][2],csp[i][j][0],csp[i][j][1]))
			roots = cubic_solver(0, 3*ax, 2*bx, cx)	 + [0,1]
			for root in roots :
				if type(root) is complex and abs(root.imag)<1e-10:
					root = root.real
				if type(root) is not complex and 0<=root<=1:
					y = ay*(root**3)+by*(root**2)+cy*root+y0  
					x = ax*(root**3)+bx*(root**2)+cx*root+x0  
					maxx = max([x,y,i,j,root],maxx)
					minx = min([x,y,i,j,root],minx)

			roots = cubic_solver(0, 3*ay, 2*by, cy)	 + [0,1]
			for root in roots :
				if type(root) is complex and root.imag==0:
					root = root.real
				if type(root) is not complex and 0<=root<=1:
					y = ay*(root**3)+by*(root**2)+cy*root+y0  
					x = ax*(root**3)+bx*(root**2)+cx*root+x0  
					maxy = max([y,x,i,j,root],maxy)
					miny = min([y,x,i,j,root],miny)
	maxy[0],maxy[1] = maxy[1],maxy[0]
	miny[0],miny[1] = miny[1],miny[0]

	return minx,miny,maxx,maxy


############################################################################
### csp_segments_intersection(sp1,sp2,sp3,sp4)
###
### Returns array containig all intersections between two segmets of cubic 
### super path. Results are [ta,tb], or [ta0, ta1, tb0, tb1, "Overlap"] 
### where ta, tb are values of t for the intersection point.
############################################################################
def csp_segments_intersection(sp1,sp2,sp3,sp4) :
	a, b = csp_segment_to_bez(sp1,sp2), csp_segment_to_bez(sp3,sp4)

	def polish_intersection(a,b,ta,tb, tolerance = intersection_tolerance) :
		ax,ay,bx,by,cx,cy,dx,dy			= bezmisc.bezierparameterize(a)
		ax1,ay1,bx1,by1,cx1,cy1,dx1,dy1	= bezmisc.bezierparameterize(b)
		i = 0
		F, F1 =  [.0,.0], [[.0,.0],[.0,.0]]
		while i==0 or (abs(F[0])**2+abs(F[1])**2 > tolerance and i<10):
			ta3, ta2, tb3, tb2 = ta**3, ta**2, tb**3, tb**2
			F[0] = ax*ta3+bx*ta2+cx*ta+dx-ax1*tb3-bx1*tb2-cx1*tb-dx1
			F[1] = ay*ta3+by*ta2+cy*ta+dy-ay1*tb3-by1*tb2-cy1*tb-dy1
			F1[0][0] =  3*ax *ta2 + 2*bx *ta + cx
			F1[0][1] = -3*ax1*tb2 - 2*bx1*tb - cx1
			F1[1][0] =  3*ay *ta2 + 2*by *ta + cy
			F1[1][1] = -3*ay1*tb2 - 2*by1*tb - cy1	
			det = F1[0][0]*F1[1][1] - F1[0][1]*F1[1][0]
			if det!=0 :
				F1 = [	[ F1[1][1]/det, -F1[0][1]/det],	[-F1[1][0]/det,  F1[0][0]/det] ]
				ta = ta - ( F1[0][0]*F[0] + F1[0][1]*F[1] )
				tb = tb - ( F1[1][0]*F[0] + F1[1][1]*F[1] )
			else: break	
			i += 1

		return ta, tb 			


	def recursion(a,b, ta0,ta1,tb0,tb1, depth_a,depth_b) :
		global bezier_intersection_recursive_result
		if a==b : 
			bezier_intersection_recursive_result += [[ta0,tb0,ta1,tb1,"Overlap"]]
			return 
		tam, tbm = (ta0+ta1)/2, (tb0+tb1)/2
		if depth_a>0 and depth_b>0 : 
			a1,a2 = bez_split(a,0.5)
			b1,b2 = bez_split(b,0.5)
			if bez_bounds_intersect(a1,b1) : recursion(a1,b1, ta0,tam,tb0,tbm, depth_a-1,depth_b-1) 
			if bez_bounds_intersect(a2,b1) : recursion(a2,b1, tam,ta1,tb0,tbm, depth_a-1,depth_b-1) 
			if bez_bounds_intersect(a1,b2) : recursion(a1,b2, ta0,tam,tbm,tb1, depth_a-1,depth_b-1) 
			if bez_bounds_intersect(a2,b2) : recursion(a2,b2, tam,ta1,tbm,tb1, depth_a-1,depth_b-1) 
		elif depth_a>0  : 
			a1,a2 = bez_split(a,0.5)
			if bez_bounds_intersect(a1,b) : recursion(a1,b, ta0,tam,tb0,tb1, depth_a-1,depth_b) 
			if bez_bounds_intersect(a2,b) : recursion(a2,b, tam,ta1,tb0,tb1, depth_a-1,depth_b) 
		elif depth_b>0  : 
			b1,b2 = bez_split(b,0.5)
			if bez_bounds_intersect(a,b1) : recursion(a,b1, ta0,ta1,tb0,tbm, depth_a,depth_b-1) 
			if bez_bounds_intersect(a,b2) : recursion(a,b2, ta0,ta1,tbm,tb1, depth_a,depth_b-1) 
		else : # Both segments have been subdevided enougth. Let's get some intersections :).
			intersection, t1, t2 =  straight_segments_intersection([a[0]]+[a[3]],[b[0]]+[b[3]])
			if intersection :
				if intersection == "Overlap" :
					t1 = ( max(0,min(1,t1[0]))+max(0,min(1,t1[1])) )/2
					t2 = ( max(0,min(1,t2[0]))+max(0,min(1,t2[1])) )/2
				bezier_intersection_recursive_result += [[ta0+t1*(ta1-ta0),tb0+t2*(tb1-tb0)]]

	global bezier_intersection_recursive_result
	bezier_intersection_recursive_result = []
	recursion(a,b,0.,1.,0.,1.,intersection_recursion_depth,intersection_recursion_depth)
	intersections = bezier_intersection_recursive_result
	for i in range(len(intersections)) :			
		if len(intersections[i])<5 or intersections[i][4] != "Overlap" :
			intersections[i] = polish_intersection(a,b,intersections[i][0],intersections[i][1])
	return intersections


def csp_segments_true_intersection(sp1,sp2,sp3,sp4) :
	intersections = csp_segments_intersection(sp1,sp2,sp3,sp4)
	res = []
	for intersection in intersections :
		if  (
				(len(intersection)==5 and intersection[4] == "Overlap" and (0<=intersection[0]<=1 or 0<=intersection[1]<=1) and (0<=intersection[2]<=1 or 0<=intersection[3]<=1) ) 
			 or ( 0<=intersection[0]<=1 and 0<=intersection[1]<=1 )
			) :
			res += [intersection]
	return res


def csp_get_t_at_curvature(sp1,sp2,c, sample_points = 16):
	# returns a list containning [t1,t2,t3,...,tn],  0<=ti<=1...
	if sample_points < 2 : sample_points = 2
	tolerance = .0000000001
	res = []
	ax,ay,bx,by,cx,cy,dx,dy = csp_parameterize(sp1,sp2)
	for k in range(sample_points) :
		t = float(k)/(sample_points-1)
		i, F = 0, 1e100
		while i<2 or abs(F)>tolerance and i<17 :
			try : # some numerical calculation could exceed the limits 
				t2 = t*t
				#slopes...
				f1x = 3*ax*t2+2*bx*t+cx
				f1y = 3*ay*t2+2*by*t+cy
				f2x = 6*ax*t+2*bx
				f2y = 6*ay*t+2*by
				f3x = 6*ax
				f3y = 6*ay
				d = (f1x**2+f1y**2)**1.5
				F1 = (
						 (	(f1x*f3y-f3x*f1y)*d - (f1x*f2y-f2x*f1y)*3.*(f2x*f1x+f2y*f1y)*((f1x**2+f1y**2)**.5) )	/ 
				 				((f1x**2+f1y**2)**3)
					 )
				F = (f1x*f2y-f1y*f2x)/d - c
				t -= F/F1
			except:
				break
			i += 1
		if 0<=t<=1 and F<=tolerance:
			if len(res) == 0 :
				res.append(t)
			for i in res : 
				if abs(t-i)<=0.001 :
					break
			if not abs(t-i)<=0.001 :
				res.append(t)
	return res	
		
	
def csp_max_curvature(sp1,sp2):
	ax,ay,bx,by,cx,cy,dx,dy = csp_parameterize(sp1,sp2)
	tolerance = .0001
	F = 0.
	i = 0
	while i<2 or F-Flast<tolerance and i<10 :
		t = .5
		f1x = 3*ax*t**2 + 2*bx*t + cx
		f1y = 3*ay*t**2 + 2*by*t + cy
		f2x = 6*ax*t + 2*bx
		f2y = 6*ay*t + 2*by
		f3x = 6*ax
		f3y = 6*ay
		d = pow(f1x**2+f1y**2,1.5)
		if d != 0 :
			Flast = F
			F = (f1x*f2y-f1y*f2x)/d
			F1 = 	(
						 (	d*(f1x*f3y-f3x*f1y) - (f1x*f2y-f2x*f1y)*3.*(f2x*f1x+f2y*f1y)*pow(f1x**2+f1y**2,.5) )	/ 
				 				(f1x**2+f1y**2)**3
					)
			i+=1	
			if F1!=0:
				t -= F/F1
			else:
				break
		else: break
	return t			
	

def csp_curvature_at_t(sp1,sp2,t, depth = 3) :
	ax,ay,bx,by,cx,cy,dx,dy = bezmisc.bezierparameterize(csp_segment_to_bez(sp1,sp2))
	
	#curvature = (x'y''-y'x'') / (x'^2+y'^2)^1.5 
	
	f1x = 3*ax*t**2 + 2*bx*t + cx
	f1y = 3*ay*t**2 + 2*by*t + cy
	f2x = 6*ax*t + 2*bx
	f2y = 6*ay*t + 2*by
	d = (f1x**2+f1y**2)**1.5
	if d != 0 :
		return (f1x*f2y-f1y*f2x)/d
	else :
		t1 = f1x*f2y-f1y*f2x
		if t1 > 0 : return 1e100
		if t1 < 0 : return -1e100
		# Use the Lapitals rule to solve 0/0 problem for 2 times...
		t1 = 2*(bx*ay-ax*by)*t+(ay*cx-ax*cy)
		if t1 > 0 : return 1e100
		if t1 < 0 : return -1e100
		t1 = bx*ay-ax*by
		if t1 > 0 : return 1e100
		if t1 < 0 : return -1e100
		if depth>0 :
			# little hack ;^) hope it wont influence anything...
			return csp_curvature_at_t(sp1,sp2,t*1.004, depth-1)
		return 1e100

	 	
def csp_curvature_radius_at_t(sp1,sp2,t) :
	c = csp_curvature_at_t(sp1,sp2,t)
	if c == 0 : return 1e100 
	else: return 1/c


def csp_special_points(sp1,sp2) :
	# special points = curvature == 0
	ax,ay,bx,by,cx,cy,dx,dy = bezmisc.bezierparameterize((sp1[1],sp1[2],sp2[0],sp2[1]))	
	a = 3*ax*by-3*ay*bx
	b = 3*ax*cy-3*cx*ay
	c = bx*cy-cx*by
	roots = cubic_solver(0, a, b, c)	
	res = []
	for i in roots :
		if type(i) is complex and i.imag==0:
			i = i.real
		if type(i) is not complex and 0<=i<=1:
			res.append(i)
	return res

	
def csp_subpath_ccw(subpath):
	# Remove all zerro length segments
	s = 0
	#subpath = subpath[:]
	if (P(subpath[-1][1])-P(subpath[0][1])).l2() > 1e-10 :
		subpath[-1][2] = subpath[-1][1]
		subpath[0][0] = subpath[0][1]
		subpath += [ [subpath[0][1],subpath[0][1],subpath[0][1]]  ]
	pl = subpath[-1][2]
	for sp1 in subpath:
		for p in sp1 :
			s += (p[0]-pl[0])*(p[1]+pl[1])
			pl = p
	return s<0


def csp_at_t(sp1,sp2,t):
	ax,bx,cx,dx = sp1[1][0], sp1[2][0], sp2[0][0], sp2[1][0]
	ay,by,cy,dy = sp1[1][1], sp1[2][1], sp2[0][1], sp2[1][1]

	x1, y1 = ax+(bx-ax)*t, ay+(by-ay)*t	
	x2, y2 = bx+(cx-bx)*t, by+(cy-by)*t	
	x3, y3 = cx+(dx-cx)*t, cy+(dy-cy)*t	
	
	x4,y4 = x1+(x2-x1)*t, y1+(y2-y1)*t 
	x5,y5 = x2+(x3-x2)*t, y2+(y3-y2)*t 
	
	x,y = x4+(x5-x4)*t, y4+(y5-y4)*t 
	return [x,y]

def csp_at_length(sp1,sp2,l=0.5, tolerance = 0.01):
	bez = (sp1[1][:],sp1[2][:],sp2[0][:],sp2[1][:])
	t = bezmisc.beziertatlength(bez, l, tolerance)
	return csp_at_t(sp1,sp2,t)
	

def csp_splitatlength(sp1, sp2, l = 0.5, tolerance = 0.01):
	bez = (sp1[1][:],sp1[2][:],sp2[0][:],sp2[1][:])
	t = bezmisc.beziertatlength(bez, l, tolerance)
	return csp_split(sp1, sp2, t)	

	
def cspseglength(sp1,sp2, tolerance = 0.01):
	bez = (sp1[1][:],sp1[2][:],sp2[0][:],sp2[1][:])
	return bezmisc.bezierlength(bez, tolerance)	


def csplength(csp):
	total = 0
	lengths = []
	for sp in csp:
		for i in xrange(1,len(sp)):
			l = cspseglength(sp[i-1],sp[i])
			lengths.append(l)
			total += l			
	return lengths, total


def csp_segments(csp):
	l, seg = 0, [0]
	for sp in csp:
		for i in xrange(1,len(sp)):
			l += cspseglength(sp[i-1],sp[i])
			seg += [ l ] 

	if l>0 :
		seg = [seg[i]/l for i in xrange(len(seg))]
	return seg,l


def rebuild_csp (csp, segs, s=None):
	# rebuild_csp() adds to csp control points making it's segments looks like segs
	if s==None : s, l = csp_segments(csp)
	
	if len(s)>len(segs) : return None
	segs = segs[:]
	segs.sort()
	for i in xrange(len(s)):
		d = None
		for j in xrange(len(segs)):
			d = min( [abs(s[i]-segs[j]),j], d) if d!=None else [abs(s[i]-segs[j]),j]
		del segs[d[1]]
	for i in xrange(len(segs)):
		for j in xrange(0,len(s)):
			if segs[i]<s[j] : break
		if s[j]-s[j-1] != 0 :
			t = (segs[i] - s[j-1])/(s[j]-s[j-1])
			sp1,sp2,sp3 = csp_split(csp[j-1],csp[j], t)
			csp = csp[:j-1] + [sp1,sp2,sp3] + csp[j+1:]
			s = s[:j] + [ s[j-1]*(1-t)+s[j]*t   ] + s[j:]
	return csp, s


def csp_slope(sp1,sp2,t):
	bez = (sp1[1][:],sp1[2][:],sp2[0][:],sp2[1][:])
	return bezmisc.bezierslopeatt(bez,t)


def csp_line_intersection(l1,l2,sp1,sp2):
	dd=l1[0]
	cc=l2[0]-l1[0]
	bb=l1[1]
	aa=l2[1]-l1[1]
	if aa==cc==0 : return []
	if aa:
		coef1=cc/aa
		coef2=1
	else:
		coef1=1
		coef2=aa/cc
	bez = (sp1[1][:],sp1[2][:],sp2[0][:],sp2[1][:])
	ax,ay,bx,by,cx,cy,x0,y0=bezmisc.bezierparameterize(bez)
	a=coef1*ay-coef2*ax
	b=coef1*by-coef2*bx
	c=coef1*cy-coef2*cx
	d=coef1*(y0-bb)-coef2*(x0-dd)
	roots = cubic_solver(a,b,c,d)
	retval = []
	for i in roots :
		if type(i) is complex and abs(i.imag)<1e-7:
			i = i.real
		if type(i) is not complex and -1e-10<=i<=1.+1e-10:
			retval.append(i)
	return retval


def csp_split_by_two_points(sp1,sp2,t1,t2) :
	if t1>t2 : t1, t2 = t2, t1
	if t1 == t2 : 
		sp1,sp2,sp3 =  csp_split(sp1,sp2,t)
		return [sp1,sp2,sp2,sp3]
	elif t1 <= 1e-10 and t2 >= 1.-1e-10 :
		return [sp1,sp1,sp2,sp2]
	elif t1 <= 1e-10:	
		sp1,sp2,sp3 = csp_split(sp1,sp2,t2)
		return [sp1,sp1,sp2,sp3]
	elif t2 >= 1.-1e-10 : 
		sp1,sp2,sp3 = csp_split(sp1,sp2,t1)
		return [sp1,sp2,sp3,sp3]
	else:
		sp1,sp2,sp3 = csp_split(sp1,sp2,t1)
		sp2,sp3,sp4 = csp_split(sp2,sp3,(t2-t1)/(1-t1) )
		return [sp1,sp2,sp3,sp4]

def csp_seg_split(sp1,sp2, points):
	# points is float=t or list [t1, t2, ..., tn]
	if type(points) is float :
		points = [points]
	points.sort()
	res = [sp1,sp2]
	last_t = 0
	for t in points: 
		if 1e-10<t<1.-1e-10 :
			sp3,sp4,sp5 = csp_split(res[-2],res[-1], (t-last_t)/(1-last_t))
			last_t = t
			res[-2:] = [sp3,sp4,sp5]
	return res		


def csp_subpath_split_by_points(subpath, points) :
	# points are [[i,t]...] where i-segment's number
	points.sort()
	points = [[1,0.]] + points + [[len(subpath)-1,1.]]
	parts = []
	for int1,int2 in zip(points,points[1:]) : 
		if int1==int2 :
			continue
		if int1[1] == 1. :
			int1[0] += 1
			int1[1] = 0.
		if int1==int2 :
			continue
		if int2[1] == 0. :
			int2[0] -= 1
			int2[1] = 1.
		if int1[0] == 0 and int2[0]==len(subpath)-1:# and small(int1[1]) and small(int2[1]-1) :
			continue
		if int1[0]==int2[0] :	# same segment
			sp = csp_split_by_two_points(subpath[int1[0]-1],subpath[int1[0]],int1[1], int2[1])
			if sp[1]!=sp[2] :
				parts += [   [sp[1],sp[2]]     ]
		else :
			sp5,sp1,sp2 = csp_split(subpath[int1[0]-1],subpath[int1[0]],int1[1])
			sp3,sp4,sp5 = csp_split(subpath[int2[0]-1],subpath[int2[0]],int2[1])
			if int1[0]==int2[0]-1 :
				parts += [	[sp1, [sp2[0],sp2[1],sp3[2]], sp4]  ]
			else :
				parts += [  [sp1,sp2]+subpath[int1[0]+1:int2[0]-1]+[sp3,sp4]  ]
	return parts


def arc_from_s_r_n_l(s,r,n,l) :
	if abs(n[0]**2+n[1]**2 - 1) > 1e-10 : n = normalize(n)
	return arc_from_c_s_l([s[0]+n[0]*r, s[1]+n[1]*r],s,l)


def arc_from_c_s_l(c,s,l) :
	r = point_to_point_d(c,s)
	if r == 0 : return []
	alpha = l/r 
	cos_, sin_ = math.cos(alpha), math.sin(alpha)
	e = [ c[0] + (s[0]-c[0])*cos_ - (s[1]-c[1])*sin_, c[1] + (s[0]-c[0])*sin_ + (s[1]-c[1])*cos_]
	n = [c[0]-s[0],c[1]-s[1]]
	slope = rotate_cw(n) if l>0 else rotate_ccw(n)
	return csp_from_arc(s, e, c, r, slope)


def csp_from_arc(start, end, center, r, slope_st) : 
	# Creates csp that approximise specified arc
	r = abs(r)
	alpha = (atan2(end[0]-center[0],end[1]-center[1]) - atan2(start[0]-center[0],start[1]-center[1])) % math.pi2

	sectors = int(abs(alpha)*2/math.pi)+1
	alpha_start = atan2(start[0]-center[0],start[1]-center[1])
	cos_,sin_ = math.cos(alpha_start), math.sin(alpha_start)
	k = (4.*math.tan(alpha/sectors/4.)/3.)
	if dot(slope_st , [- sin_*k*r, cos_*k*r]) < 0 :
		if alpha>0 : alpha -= math.pi2
		else: alpha += math.pi2
	if abs(alpha*r)<0.001 : 
		return []

	sectors = int(abs(alpha)*2/math.pi)+1
	k = (4.*math.tan(alpha/sectors/4.)/3.)
	result = []
	for i in range(sectors+1) :
		cos_,sin_ = math.cos(alpha_start + alpha*i/sectors), math.sin(alpha_start + alpha*i/sectors)
		sp = [ [], [center[0] + cos_*r, center[1] + sin_*r], [] ]
		sp[0] = [sp[1][0] + sin_*k*r, sp[1][1] - cos_*k*r ]
		sp[2] = [sp[1][0] - sin_*k*r, sp[1][1] + cos_*k*r ]
		result += [sp]
	result[0][0] = result[0][1][:]
	result[-1][2] = result[-1][1]
		
	return result


def point_to_arc_distance(p, arc):
	###		Distance calculattion from point to arc
	P0,P2,c,a = arc
	dist = None
	p = P(p)
	r = (P0-c).mag()
	if r>0 :
		i = c + (p-c).unit()*r
		alpha = ((i-c).angle() - (P0-c).angle())
		if a*alpha<0: 
			if alpha>0:	alpha = alpha-math.pi2
			else: alpha = math.pi2+alpha
		if between(alpha,0,a) or min(abs(alpha),abs(alpha-a))<straight_tolerance : 
			return (p-i).mag(), [i.x, i.y]
		else : 
			d1, d2 = (p-P0).mag(), (p-P2).mag()
			if d1<d2 : 
				return (d1, [P0.x,P0.y])
			else :
				return (d2, [P2.x,P2.y])


def csp_to_arc_distance(sp1,sp2, arc1, arc2, tolerance = 0.01 ): # arc = [start,end,center,alpha]
	n, i = 10, 0
	d, d1, dl = (0,(0,0)), (0,(0,0)), 0
	while i<1 or (abs(d1[0]-dl[0])>tolerance and i<4):
		i += 1
		dl = d1*1	
		for j in range(n+1):
			t = float(j)/n
			p = csp_at_t(sp1,sp2,t) 
			d = min(point_to_arc_distance(p,arc1), point_to_arc_distance(p,arc2))
			d1 = max(d1,d)
		n=n*2
	return d1[0]


def csp_simple_bound_to_point_distance(p, csp):
	minx,miny,maxx,maxy = None,None,None,None
	for subpath in csp:
		for sp in subpath:
			for p_ in sp:
				minx = min(minx,p_[0]) if minx!=None else p_[0]
				miny = min(miny,p_[1]) if miny!=None else p_[1]
				maxx = max(maxx,p_[0]) if maxx!=None else p_[0]
				maxy = max(maxy,p_[1]) if maxy!=None else p_[1]
	return math.sqrt(max(minx-p[0],p[0]-maxx,0)**2+max(miny-p[1],p[1]-maxy,0)**2)


def csp_point_inside_bound(sp1, sp2, p):
	bez = [sp1[1],sp1[2],sp2[0],sp2[1]]
	x,y = p
	c = 0
	#CLT added test of x in range
	xmin=1e100
	xmax=-1e100
	for i in range(4):
		[x0,y0], [x1,y1] = bez[i-1], bez[i]
		xmin=min(xmin,x0)
		xmax=max(xmax,x0)
		if x0-x1!=0 and (y-y0)*(x1-x0)>=(x-x0)*(y1-y0) and x>min(x0,x1) and x<=max(x0,x1) :
			c +=1
	return xmin<=x<=xmax and c%2==0	


def csp_bound_to_point_distance(sp1, sp2, p):
	if csp_point_inside_bound(sp1, sp2, p) :
		return 0.
	bez = csp_segment_to_bez(sp1,sp2)
	min_dist = 1e100
	for i in range(0,4):
		d = point_to_line_segment_distance_2(p, bez[i-1],bez[i])
		if d <= min_dist : min_dist = d
	return min_dist 


def line_line_intersect(p1,p2,p3,p4) : # Return only true intersection. 
	if (p1[0]==p2[0] and p1[1]==p2[1]) or (p3[0]==p4[0] and p3[1]==p4[1]) : return False
	x = (p2[0]-p1[0])*(p4[1]-p3[1]) - (p2[1]-p1[1])*(p4[0]-p3[0])
	if x==0 : # Lines are parallel
		if (p3[0]-p1[0])*(p2[1]-p1[1]) == (p3[1]-p1[1])*(p2[0]-p1[0]) :
			if p3[0]!=p4[0] :
				t11 = (p1[0]-p3[0])/(p4[0]-p3[0]) 
				t12 = (p2[0]-p3[0])/(p4[0]-p3[0]) 
				t21 = (p3[0]-p1[0])/(p2[0]-p1[0])
				t22 = (p4[0]-p1[0])/(p2[0]-p1[0])
			else:
				t11 = (p1[1]-p3[1])/(p4[1]-p3[1]) 
				t12 = (p2[1]-p3[1])/(p4[1]-p3[1]) 
				t21 = (p3[1]-p1[1])/(p2[1]-p1[1])
				t22 = (p4[1]-p1[1])/(p2[1]-p1[1])
			return ("Overlap" if (0<=t11<=1 or 0<=t12<=1) and (0<=t21<=1 or  0<=t22<=1) else False)
		else: return False	
	else :
		return (
					0<=((p4[0]-p3[0])*(p1[1]-p3[1]) - (p4[1]-p3[1])*(p1[0]-p3[0]))/x<=1 and
					0<=((p2[0]-p1[0])*(p1[1]-p3[1]) - (p2[1]-p1[1])*(p1[0]-p3[0]))/x<=1 )
					
					
def line_line_intersection_points(p1,p2,p3,p4) : # Return only points [ (x,y) ] 
	if (p1[0]==p2[0] and p1[1]==p2[1]) or (p3[0]==p4[0] and p3[1]==p4[1]) : return []
	x = (p2[0]-p1[0])*(p4[1]-p3[1]) - (p2[1]-p1[1])*(p4[0]-p3[0])
	if x==0 : # Lines are parallel
		if (p3[0]-p1[0])*(p2[1]-p1[1]) == (p3[1]-p1[1])*(p2[0]-p1[0]) :
			if p3[0]!=p4[0] :
				t11 = (p1[0]-p3[0])/(p4[0]-p3[0]) 
				t12 = (p2[0]-p3[0])/(p4[0]-p3[0]) 
				t21 = (p3[0]-p1[0])/(p2[0]-p1[0])
				t22 = (p4[0]-p1[0])/(p2[0]-p1[0])
			else:
				t11 = (p1[1]-p3[1])/(p4[1]-p3[1]) 
				t12 = (p2[1]-p3[1])/(p4[1]-p3[1]) 
				t21 = (p3[1]-p1[1])/(p2[1]-p1[1])
				t22 = (p4[1]-p1[1])/(p2[1]-p1[1])
			res = [] 
			if (0<=t11<=1 or 0<=t12<=1) and (0<=t21<=1 or  0<=t22<=1) :
				if 0<=t11<=1 : res += [p1]	
				if 0<=t12<=1 : res += [p2]	
				if 0<=t21<=1 : res += [p3]	
				if 0<=t22<=1 : res += [p4]	
			return res
		else: return []
	else :
		t1 = ((p4[0]-p3[0])*(p1[1]-p3[1]) - (p4[1]-p3[1])*(p1[0]-p3[0]))/x
		t2 = ((p2[0]-p1[0])*(p1[1]-p3[1]) - (p2[1]-p1[1])*(p1[0]-p3[0]))/x
		if 0<=t1<=1 and 0<=t2<=1 : return [ [p1[0]*(1-t1)+p2[0]*t1, p1[1]*(1-t1)+p2[1]*t1] ]
		else : return []					


def point_to_point_d2(a,b):
	return (a[0]-b[0])**2 + (a[1]-b[1])**2


def point_to_point_d(a,b):
	return math.sqrt((a[0]-b[0])**2 + (a[1]-b[1])**2)


def point_to_line_segment_distance_2(p1, p2,p3) :
	# p1 - point, p2,p3 - line segment
	#draw_pointer(p1)
	w0 = [p1[0]-p2[0], p1[1]-p2[1]]
	v = [p3[0]-p2[0], p3[1]-p2[1]]
	c1 = w0[0]*v[0] + w0[1]*v[1]
	if c1 <= 0 :
		return w0[0]*w0[0]+w0[1]*w0[1]
	c2 = v[0]*v[0] + v[1]*v[1]
	if c2 <= c1 :
		return  (p1[0]-p3[0])**2 + (p1[1]-p3[1])**2
	return (p1[0]- p2[0]-v[0]*c1/c2)**2 + (p1[1]- p2[1]-v[1]*c1/c2)


def line_to_line_distance_2(p1,p2,p3,p4):
	if line_line_intersect(p1,p2,p3,p4) : return 0
	return min(
			point_to_line_segment_distance_2(p1,p3,p4),
			point_to_line_segment_distance_2(p2,p3,p4),
			point_to_line_segment_distance_2(p3,p1,p2),
			point_to_line_segment_distance_2(p4,p1,p2))


def csp_seg_bound_to_csp_seg_bound_max_min_distance(sp1,sp2,sp3,sp4) :
	bez1 = csp_segment_to_bez(sp1,sp2)
	bez2 = csp_segment_to_bez(sp3,sp4) 
	min_dist = 1e100
	max_dist = 0.
	for i in range(4) :
		if csp_point_inside_bound(sp1, sp2, bez2[i]) or csp_point_inside_bound(sp3, sp4, bez1[i]) :
			min_dist = 0.
			break	
	for i in range(4) : 
		for j in range(4) : 
			d = line_to_line_distance_2(bez1[i-1],bez1[i],bez2[j-1],bez2[j])
			if d < min_dist : min_dist = d
			d = (bez2[j][0]-bez1[i][0])**2 + (bez2[j][1]-bez1[i][1])**2 
			if max_dist < d  : max_dist = d
	return min_dist, max_dist


def csp_reverse(csp) :
	for i in range(len(csp)) :
	 	n = []
	 	for j in csp[i] :
			n = [  [j[2][:],j[1][:],j[0][:]]  ] + n
	 	csp[i] = n[:]
	return csp			


def csp_normalized_slope(sp1,sp2,t) :
	ax,ay,bx,by,cx,cy,dx,dy=bezmisc.bezierparameterize((sp1[1][:],sp1[2][:],sp2[0][:],sp2[1][:]))
	if sp1[1]==sp2[1]==sp1[2]==sp2[0] : return [1.,0.]
	f1x = 3*ax*t*t+2*bx*t+cx
	f1y = 3*ay*t*t+2*by*t+cy
	if abs(f1x*f1x+f1y*f1y) > 1e-9 : #LT changed this from 1e-20, which caused problems
		l = math.sqrt(f1x*f1x+f1y*f1y)
		return [f1x/l, f1y/l]

	if t == 0 :
		f1x = sp2[0][0]-sp1[1][0]
		f1y = sp2[0][1]-sp1[1][1]
		if abs(f1x*f1x+f1y*f1y) > 1e-9 : #LT changed this from 1e-20, which caused problems
			l = math.sqrt(f1x*f1x+f1y*f1y)
			return [f1x/l, f1y/l]
		else :
			f1x = sp2[1][0]-sp1[1][0]
			f1y = sp2[1][1]-sp1[1][1]
			if f1x*f1x+f1y*f1y != 0 :
				l = math.sqrt(f1x*f1x+f1y*f1y)
				return [f1x/l, f1y/l]
	elif t == 1 :
		f1x = sp2[1][0]-sp1[2][0]
		f1y = sp2[1][1]-sp1[2][1]
		if abs(f1x*f1x+f1y*f1y) > 1e-9 :
			l = math.sqrt(f1x*f1x+f1y*f1y)
			return [f1x/l, f1y/l]
		else :
			f1x = sp2[1][0]-sp1[1][0]
			f1y = sp2[1][1]-sp1[1][1]
			if f1x*f1x+f1y*f1y != 0 :
				l = math.sqrt(f1x*f1x+f1y*f1y)
				return [f1x/l, f1y/l]
	else :
		return [1.,0.]

				
def csp_normalized_normal(sp1,sp2,t) :
	nx,ny = csp_normalized_slope(sp1,sp2,t)
	return [-ny, nx]


def csp_parameterize(sp1,sp2):
	return bezmisc.bezierparameterize(csp_segment_to_bez(sp1,sp2))


def csp_concat_subpaths(*s):
	
	def concat(s1,s2) :
		if s1 == [] : return s2
		if s2 == [] : return s1
		if (s1[-1][1][0]-s2[0][1][0])**2 + (s1[-1][1][1]-s2[0][1][1])**2 > 0.00001 :
	 		return s1[:-1]+[ [s1[-1][0],s1[-1][1],s1[-1][1]],  [s2[0][1],s2[0][1],s2[0][2]] ] + s2[1:]		
	 	else :
	 		return s1[:-1]+[ [s1[-1][0],s2[0][1],s2[0][2]] ] + s2[1:]		
	 		
	if len(s) == 0 : return []
	if len(s) ==1 : return s[0]
	result = s[0]
	for s1 in s[1:]:
		result = concat(result,s1)
	return result

def csp_subpaths_end_to_start_distance2(s1,s2):
	return (s1[-1][1][0]-s2[0][1][0])**2 + (s1[-1][1][1]-s2[0][1][1])**2


def csp_clip_by_line(csp,l1,l2) :
	result = []
	for i in range(len(csp)):
		s = csp[i]
		intersections = []
		for j in range(1,len(s)) :
			intersections += [  [j,int_] for int_ in csp_line_intersection(l1,l2,s[j-1],s[j])]
		splitted_s = csp_subpath_split_by_points(s, intersections)
		for s in splitted_s[:] :
			clip = False
			for p in csp_true_bounds([s]) :
				if (l1[1]-l2[1])*p[0] + (l2[0]-l1[0])*p[1] + (l1[0]*l2[1]-l2[0]*l1[1])<-0.01 : 
					clip = True
					break
			if clip :
				splitted_s.remove(s)
		result += splitted_s
	return result


def csp_subpath_line_to(subpath, points, prepend = False) :
	# Appends subpath with line or polyline.
	if len(points)>0 :
		if not prepend : 
			if len(subpath)>0:
				subpath[-1][2] = subpath[-1][1][:]
			if type(points[0]) == type([1,1]) :
				for p in points :
					subpath += [ [p[:],p[:],p[:]] ]
			else: 
				subpath += [ [points,points,points] ]
		else : 		
			if len(subpath)>0:
				subpath[0][0] = subpath[0][1][:]
			if type(points[0]) == type([1,1]) :
				for p in points :
					subpath = [ [p[:],p[:],p[:]] ] + subpath
			else: 
				subpath = [ [points,points,points] ] + subpath
	return subpath

	
def csp_join_subpaths(csp) :
	result = csp[:]
	done_smf = True
	joined_result = []
	while done_smf :
		done_smf = False
		while len(result)>0:
			s1 = result[-1][:]
			del(result[-1])
			j = 0
			joined_smf = False
			while j<len(joined_result) :
				if csp_subpaths_end_to_start_distance2(joined_result[j],s1) <0.000001 :
					joined_result[j] = csp_concat_subpaths(joined_result[j],s1)
					done_smf = True
					joined_smf = True
					break				
				if csp_subpaths_end_to_start_distance2(s1,joined_result[j]) <0.000001 :
					joined_result[j] = csp_concat_subpaths(s1,joined_result[j])
					done_smf = True
					joined_smf = True
					break				
				j += 1
			if not joined_smf : joined_result += [s1[:]]
		if done_smf : 
			result = joined_result[:]
			joined_result = []
	return joined_result


def triangle_cross(a,b,c):
	return (a[0]-b[0])*(c[1]-b[1]) - (c[0]-b[0])*(a[1]-b[1])
	

def csp_segment_convex_hull(sp1,sp2):
	a,b,c,d = sp1[1][:], sp1[2][:], sp2[0][:], sp2[1][:]
	
	abc = triangle_cross(a,b,c)
	abd = triangle_cross(a,b,d)
	bcd = triangle_cross(b,c,d)
	cad = triangle_cross(c,a,d)
	if abc == 0 and abd == 0 : return [min(a,b,c,d), max(a,b,c,d)]
	if abc == 0 : return [d, min(a,b,c), max(a,b,c)]
	if abd == 0 : return [c, min(a,b,d), max(a,b,d)]
	if bcd == 0 : return [a, min(b,c,d), max(b,c,d)]
	if cad == 0 : return [b, min(c,a,d), max(c,a,d)]
	
	m1, m2, m3  =  abc*abd>0, abc*bcd>0, abc*cad>0
	if m1 and m2 and m3 : return [a,b,c]
	if     m1 and     m2 and not m3 : return [a,b,c,d]
	if     m1 and not m2 and     m3 : return [a,b,d,c]
	if not m1 and     m2 and     m3 : return [a,d,b,c]
	if m1 and not (m2 and m3) : return [a,b,d]
	if not (m1 and m2) and m3 : return [c,a,d]
	if not (m1 and m3) and m2 : return [b,c,d]
	
	raise ValueError, "csp_segment_convex_hull happend something that shouldnot happen!"	

	
################################################################################
###		Bezier additional functions
################################################################################

def bez_bounds_intersect(bez1, bez2) :
	return bounds_intersect(bez_bound(bez2), bez_bound(bez1))


def bez_bound(bez) :
	return [
				min(bez[0][0], bez[1][0], bez[2][0], bez[3][0]),
				min(bez[0][1], bez[1][1], bez[2][1], bez[3][1]),
				max(bez[0][0], bez[1][0], bez[2][0], bez[3][0]),
				max(bez[0][1], bez[1][1], bez[2][1], bez[3][1]),
			]


def bounds_intersect(a, b) :
	return not ( (a[0]>b[2]) or (b[0]>a[2]) or (a[1]>b[3]) or (b[1]>a[3]) )


def tpoint((x1,y1),(x2,y2),t):
	return [x1+t*(x2-x1),y1+t*(y2-y1)]


def bez_to_csp_segment(bez) :
	return [bez[0],bez[0],bez[1]], [bez[2],bez[3],bez[3]]


def bez_split(a,t=0.5) :
	 a1 = tpoint(a[0],a[1],t)
	 at = tpoint(a[1],a[2],t)
	 b2 = tpoint(a[2],a[3],t)
	 a2 = tpoint(a1,at,t)
	 b1 = tpoint(b2,at,t)
	 a3 = tpoint(a2,b1,t)
	 return [a[0],a1,a2,a3], [a3,b1,b2,a[3]]

	
def bez_at_t(bez,t) :
	return csp_at_t([bez[0],bez[0],bez[1]],[bez[2],bez[3],bez[3]],t)


def bez_to_point_distance(bez,p,needed_dist=[0.,1e100]):
	# returns [d^2,t]
	return csp_seg_to_point_distance(bez_to_csp_segment(bez),p,needed_dist)


def bez_normalized_slope(bez,t):
	return csp_normalized_slope([bez[0],bez[0],bez[1]], [bez[2],bez[3],bez[3]],t)	

################################################################################
###	Some vector functions
################################################################################
	
def normalize((x,y)) :
	l = math.sqrt(x**2+y**2)
	if l == 0 : return [0.,0.]
	else : 		return [x/l, y/l]


def cross(a,b) :
	return a[1] * b[0] - a[0] * b[1]


def dot(a,b) :
	return a[0] * b[0] + a[1] * b[1]


def rotate_ccw(d) :
	return [-d[1],d[0]]

def rotate_cw(d) :
	return [d[1],-d[0]]


def vectors_ccw(a,b):
	return a[0]*b[1]-b[0]*a[1] < 0

def vector_add(a,b) :
	return [a[0]+b[0],a[1]+b[1]]

def vector_mul(a,b) :
	return [a[0]*b,a[1]*b]


def vector_from_to_length(a,b):
	return math.sqrt((a[0]-b[0])*(a[0]-b[0]) + (a[1]-b[1])*(a[1]-b[1]))

################################################################################
###	Common functions
################################################################################

def matrix_mul(a,b) :
	return [ [ sum([a[i][k]*b[k][j] for k in range(len(a[0])) ])   for j in range(len(b[0]))]   for i in range(len(a))] 
	try :
		return [ [ sum([a[i][k]*b[k][j] for k in range(len(a[0])) ])   for j in range(len(b[0]))]   for i in range(len(a))] 
	except :
		return None


def transpose(a) :
	try :
		return [ [ a[i][j] for i in range(len(a)) ] for j in range(len(a[0])) ]
	except :
		return None


def det_3x3(a):
	return  float(
		a[0][0]*a[1][1]*a[2][2] + a[0][1]*a[1][2]*a[2][0] + a[1][0]*a[2][1]*a[0][2]
		- a[0][2]*a[1][1]*a[2][0] - a[0][0]*a[2][1]*a[1][2] - a[0][1]*a[2][2]*a[1][0]
		)


def inv_3x3(a): # invert matrix 3x3
	det = det_3x3(a)
	if det==0: return None
	return	[  
		[  (a[1][1]*a[2][2] - a[2][1]*a[1][2])/det,  -(a[0][1]*a[2][2] - a[2][1]*a[0][2])/det,  (a[0][1]*a[1][2] - a[1][1]*a[0][2])/det ], 
		[ -(a[1][0]*a[2][2] - a[2][0]*a[1][2])/det,   (a[0][0]*a[2][2] - a[2][0]*a[0][2])/det, -(a[0][0]*a[1][2] - a[1][0]*a[0][2])/det ], 
		[  (a[1][0]*a[2][1] - a[2][0]*a[1][1])/det,  -(a[0][0]*a[2][1] - a[2][0]*a[0][1])/det,  (a[0][0]*a[1][1] - a[1][0]*a[0][1])/det ]
	]


def inv_2x2(a): # invert matrix 2x2
	det = a[0][0]*a[1][1] - a[1][0]*a[0][1]
	if det==0: return None
	return [
			[a[1][1]/det, -a[0][1]/det],
			[-a[1][0]/det, a[0][0]/det]
			]


def small(a) :
	global small_tolerance
	return abs(a)<small_tolerance

					
def atan2(*arg):	
	if len(arg)==1 and ( type(arg[0]) == type([0.,0.]) or type(arg[0])==type((0.,0.)) ) :
		return (math.pi/2 - math.atan2(arg[0][0], arg[0][1]) ) % math.pi2
	elif len(arg)==2 :
		
		return (math.pi/2 - math.atan2(arg[0],arg[1]) ) % math.pi2
	else :
		raise ValueError, "Bad argumets for atan! (%s)" % arg  

def get_text(node) :
	value = None
	if node.text!=None : value = value +"\n" + node.text if value != None else node.text
	for k in node :
		if k.tag == inkex.addNS('tspan','svg'):
			if k.text!=None : value = value +"\n" + k.text if value != None else k.text
	return value



def draw_text(text,x,y, group = None, style = None, font_size = 10, gcodetools_tag = None) :
	if style == None : 
		style = "font-family:DejaVu Sans;font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;font-family:DejaVu Sans;fill:#000000;fill-opacity:1;stroke:none;"
	style += "font-size:%fpx;"%font_size
	attributes = {			'x':	str(x),
							inkex.addNS("space","xml"):"preserve",
							'y':	str(y),
							'style' : style
						}
	if gcodetools_tag!=None : 
		attributes["gcodetools"] = str(gcodetools_tag)
 
	if group == None:
		group = options.doc_root

	t = inkex.etree.SubElement(	group, inkex.addNS('text','svg'), attributes)
	text = str(text).split("\n")
	for s in text :
		span = inkex.etree.SubElement( t, inkex.addNS('tspan','svg'), 
						{
							'x':	str(x),
							'y':	str(y),
							inkex.addNS("role","sodipodi"):"line",
						})					
		y += font_size
		span.text = str(s)

def draw_csp(csp, stroke = "#f00", fill = "none", comment = "", width = 0.354, group = None, style = None, gcodetools_tag = None) :
	if style == None : 
		style = "fill:%s;fill-opacity:1;stroke:%s;stroke-width:%s"%(fill,stroke,width)
	attributes = {			'd':	cubicsuperpath.formatPath(csp),
							'style' : style
				}
	if comment != '':
		attributes['comment'] = comment
	if group == None :
		group = options.doc_root
		
	return inkex.etree.SubElement( group, inkex.addNS('path','svg'), attributes) 
	
def draw_pointer(x,color = "#f00", figure = "cross", group = None, comment = "", fill=None, width = .1, size = 10., text = None, font_size=None, pointer_type=None, attrib = None) :
	size = size/2
	if attrib == None : attrib = {}
	if pointer_type == None: 
		pointer_type = "Pointer"
	attrib["gcodetools"] = pointer_type
	if group == None:
		group = options.self.current_layer
	if text != None	:
		if font_size == None : font_size = 7
		group = inkex.etree.SubElement( group, inkex.addNS('g','svg'), {"gcodetools": pointer_type+" group"} )		
		draw_text(text,x[0]+size*2.2,x[1]-size, group = group, font_size = font_size) 
	if figure  == "line" :
		s = ""
		for i in range(1,len(x)/2) :
			s+= " %s, %s " %(x[i*2],x[i*2+1])
		attrib.update({"d": "M %s,%s L %s"%(x[0],x[1],s), "style":"fill:none;stroke:%s;stroke-width:%f;"%(color,width),"comment":str(comment)})			
		inkex.etree.SubElement( group, inkex.addNS('path','svg'), attrib)
	elif figure == "arrow" :
		if fill == None : fill = "#12b3ff"
		fill_opacity = "0.8" 
		d = "m %s,%s " % (x[0],x[1]) + re.sub("([0-9\-.e]+)",(lambda match: str(float(match.group(1))*size*2.)), "0.88464,-0.40404 c -0.0987,-0.0162 -0.186549,-0.0589 -0.26147,-0.1173 l 0.357342,-0.35625 c 0.04631,-0.039 0.0031,-0.13174 -0.05665,-0.12164 -0.0029,-1.4e-4 -0.0058,-1.4e-4 -0.0087,0 l -2.2e-5,2e-5 c -0.01189,0.004 -0.02257,0.0119 -0.0305,0.0217 l -0.357342,0.35625 c -0.05818,-0.0743 -0.102813,-0.16338 -0.117662,-0.26067 l -0.409636,0.88193 z")
		attrib.update({"d": d, "style":"fill:%s;stroke:none;fill-opacity:%s;"%(fill,fill_opacity),"comment":str(comment)})			
		inkex.etree.SubElement( group, inkex.addNS('path','svg'), attrib)
	else :
		attrib.update({"d": "m %s,%s l %f,%f %f,%f %f,%f %f,%f , %f,%f"%(x[0],x[1], size,size, -2*size,-2*size, size,size, size,-size, -2*size,2*size ), "style":"fill:none;stroke:%s;stroke-width:%f;"%(color,width),"comment":str(comment)})
		inkex.etree.SubElement( group, inkex.addNS('path','svg'), attrib)


def straight_segments_intersection(a,b, true_intersection = True) : # (True intersection means check ta and tb are in [0,1])
 	ax,bx,cx,dx, ay,by,cy,dy = a[0][0],a[1][0],b[0][0],b[1][0], a[0][1],a[1][1],b[0][1],b[1][1] 
	if (ax==bx and ay==by) or (cx==dx and cy==dy) : return False, 0, 0
	if (bx-ax)*(dy-cy)-(by-ay)*(dx-cx)==0 :	# Lines are parallel
		ta = (ax-cx)/(dx-cx) if cx!=dx else (ay-cy)/(dy-cy)
		tb = (bx-cx)/(dx-cx) if cx!=dx else (by-cy)/(dy-cy)
		tc = (cx-ax)/(bx-ax) if ax!=bx else (cy-ay)/(by-ay)
		td = (dx-ax)/(bx-ax) if ax!=bx else (dy-ay)/(by-ay)
		return ("Overlap" if 0<=ta<=1 or 0<=tb<=1 or  0<=tc<=1 or  0<=td<=1 or not true_intersection else False), (ta,tb), (tc,td)
	else :
		ta = ( (ay-cy)*(dx-cx)-(ax-cx)*(dy-cy) ) / ( (bx-ax)*(dy-cy)-(by-ay)*(dx-cx) )
		tb = ( ax-cx+ta*(bx-ax) ) / (dx-cx) if dx!=cx else ( ay-cy+ta*(by-ay) ) / (dy-cy)
		return (0<=ta<=1 and 0<=tb<=1 or not true_intersection), ta, tb
	
	

def isnan(x): return type(x) is float and x != x

def isinf(x): inf = 1e5000; return x == inf or x == -inf

def between(c,x,y):
		return x-straight_tolerance<=c<=y+straight_tolerance or y-straight_tolerance<=c<=x+straight_tolerance

def cubic_solver_real(a,b,c,d):
	# returns only real roots of a cubic equation.
	roots = cubic_solver(a,b,c,d)
	res = []
	for root in roots :
		if type(root) is complex :	
			if -1e-10<root.imag<1e-10 :
				res.append(root.real)
		else :
			res.append(root)
	return res 
	
	
def cubic_solver(a,b,c,d):	
	if a!=0:
		#	Monics formula see http://en.wikipedia.org/wiki/Cubic_function#Monic_formula_of_roots
		a,b,c = (b/a, c/a, d/a)
		m = 2*a**3 - 9*a*b + 27*c
		k = a**2 - 3*b
		n = m**2 - 4*k**3
		w1 = -.5 + .5*cmath.sqrt(3)*1j
		w2 = -.5 - .5*cmath.sqrt(3)*1j
		if n>=0 :
			t = m+math.sqrt(n)
			m1 = pow(t/2,1./3) if t>=0 else -pow(-t/2,1./3)
			t = m-math.sqrt(n)
			n1 = pow(t/2,1./3) if t>=0 else -pow(-t/2,1./3)
		else :
			m1 = pow(complex((m+cmath.sqrt(n))/2),1./3)
			n1 = pow(complex((m-cmath.sqrt(n))/2),1./3)
		x1 = -1./3 * (a + m1 + n1)
		x2 = -1./3 * (a + w1*m1 + w2*n1)
		x3 = -1./3 * (a + w2*m1 + w1*n1)
		return [x1,x2,x3]
	elif b!=0:
		det = c**2-4*b*d
		if det>0 :
			return [(-c+math.sqrt(det))/(2*b),(-c-math.sqrt(det))/(2*b)]
		elif d == 0 :
			return [-c/(b*b)] 	
		else :
			return [(-c+cmath.sqrt(det))/(2*b),(-c-cmath.sqrt(det))/(2*b)]
	elif c!=0 :
		return [-d/c]
	else : return []


################################################################################
###		print_ prints any arguments into specified log file
################################################################################

def print_(*arg):
	f = open(options.log_filename,"a")
	for s in arg :
		s = str(unicode(s).encode('unicode_escape'))+" "
		f.write( s )
	f.write("\n")
	f.close()


################################################################################
###		Point (x,y) operations
################################################################################
class P:
	def __init__(self, x, y=None):
		if not y==None:
			self.x, self.y = float(x), float(y)
		else:
			self.x, self.y = float(x[0]), float(x[1])
	def __add__(self, other): return P(self.x + other.x, self.y + other.y)
	def __sub__(self, other): return P(self.x - other.x, self.y - other.y)
	def __neg__(self): return P(-self.x, -self.y)
	def __mul__(self, other):
		if isinstance(other, P):
			return self.x * other.x + self.y * other.y
		return P(self.x * other, self.y * other)
	__rmul__ = __mul__
	def __div__(self, other): return P(self.x / other, self.y / other)
	def mag(self): return math.hypot(self.x, self.y)
	def unit(self):
		h = self.mag()
		if h: return self / h
		else: return P(0,0)
	def dot(self, other): return self.x * other.x + self.y * other.y
	def rot(self, theta):
		c = math.cos(theta)
		s = math.sin(theta)
		return P(self.x * c - self.y * s,  self.x * s + self.y * c)
	def angle(self): return math.atan2(self.y, self.x)
	def __repr__(self): return '%f,%f' % (self.x, self.y)
	def pr(self): return "%.2f,%.2f" % (self.x, self.y)
	def to_list(self): return [self.x, self.y]	
	def ccw(self): return P(-self.y,self.x)
	def l2(self): return self.x*self.x + self.y*self.y


class Arc():
	def __init__(self,st,end,c,a):
		self.st = P(st)
		self.end = P(end)
		self.c = P(c)
		self.r = (P(st)-P(c)).mag()
		self.a = ( (self.st-self.c).angle() - (self.end-self.c).angle() ) % math.pi2
		if a<0 : self.a -= math.pi2

	def offset(self, r):
		if self.a>0 :
			r += self.r
		else :
			r = self.r - r
		
		if self.r != 0 :
			self.st = self.c + (self.st-self.c)*r/self.r
			self.end = self.c + (self.end-self.c)*r/self.r
			self.r = r
	
	def length(self):
		return abs(self.a*self.r)
	

	def draw(self, group, style, layer, transform, num = 0, reverse_angle = 1):
		st = P(gcodetools.transform(self.st.to_list(), layer, True))
		c = P(gcodetools.transform(self.c.to_list(), layer, True))
		a = self.a * reverse_angle
		r = (st-c)
		a_st = (math.atan2(r.x,-r.y) - math.pi/2) % (math.pi*2)
		r = r.mag()
		if a<0:
			a_end = a_st+a
			style = style['biarc%s'%(num%2)]
		else: 
			a_end = a_st
			a_st = a_st+a
			style = style['biarc%s_r'%(num%2)]
		
		attr = {
				'style': style,
				 inkex.addNS('cx','sodipodi'):		str(c.x),
				 inkex.addNS('cy','sodipodi'):		str(c.y),
				 inkex.addNS('rx','sodipodi'):		str(r),
				 inkex.addNS('ry','sodipodi'):		str(r),
				 inkex.addNS('start','sodipodi'):	str(a_st),
				 inkex.addNS('end','sodipodi'):		str(a_end),
				 inkex.addNS('open','sodipodi'):	'true',
				 inkex.addNS('type','sodipodi'):	'arc',
				 "gcodetools": "Preview",
				}	
		if transform != [] :
			attr["transform"] = transform	
		inkex.etree.SubElement(	group, inkex.addNS('path','svg'), attr)
		
	def intersect(self,b) :
		return []


class Line():
	def __init__(self,st,end):
		if st.__class__ == P :
			st = st.to_list()
		if end.__class__ == P :
			end = end.to_list()
		self.st = P(st)
		self.end = P(end)
		self.l = self.length() 
		if self.l != 0 :
			self.n = ((self.end-self.st)/self.l).ccw()
		else: 
			self.n = [0,1]
				
	def offset(self, r):
		self.st -= self.n*r
		self.end -= self.n*r
		
	def l2(self): return (self.st-self.end).l2()
	def length(self): return (self.st-self.end).mag()
	
	def draw(self, group, style, layer, transform, num = 0, reverse_angle = 1):
		st = gcodetools.transform(self.st.to_list(), layer, True)
		end = gcodetools.transform(self.end.to_list(), layer, True)


		attr = {	'style': style['line'],
					'd':'M %s,%s L %s,%s' % (st[0],st[1],end[0],end[1]),
					"gcodetools": "Preview",
				}
		if transform != [] :
			attr["transform"] = transform		
		inkex.etree.SubElement(	group, inkex.addNS('path','svg'),  attr	)
	
	def intersect(self,b) :
		if b.__class__ == Line :
			if self.l < 10e-8 or b.l < 10e-8 : return []
			v1 = self.end - self.st
			v2 = b.end - b.st
			x = v1.x*v2.y - v2.x*v1.y 
			if x == 0 :
				# lines are parallel
				res = []

				if (self.st.x-b.st.x)*v1.y - (self.st.y-b.st.y)*v1.x  == 0:
					# lines are the same
					if v1.x != 0 :
						if 0<=(self.st.x-b.st.x)/v2.x<=1 :  res.append(self.st)
						if 0<=(self.end.x-b.st.x)/v2.x<=1 :  res.append(self.end)
						if 0<=(b.st.x-self.st.x)/v1.x<=1 :  res.append(b.st)
						if 0<=(b.end.x-b.st.x)/v1.x<=1 :  res.append(b.end)
					else :
						if 0<=(self.st.y-b.st.y)/v2.y<=1 :  res.append(self.st)
						if 0<=(self.end.y-b.st.y)/v2.y<=1 :  res.append(self.end)
						if 0<=(b.st.y-self.st.y)/v1.y<=1 :  res.append(b.st)
						if 0<=(b.end.y-b.st.y)/v1.y<=1 :  res.append(b.end)
				return res
			else :
				t1 = ( -v1.x*(b.end.y-self.end.y) + v1.y*(b.end.x-self.end.x) ) / x
				t2 = ( -v1.y*(self.st.x-b.st.x) + v1.x*(self.st.y-b.st.y) ) / x

				gcodetools.error((x,t1,t2), "warning")
				if 0<=t1<=1 and 0<=t2<=1 : return [ self.st+v1*t1 ]
				else : return []					
		else: return []	
			
			
	
	
class Biarc:
	def __init__(self, items=None):
		if items == None :
			self.items = []
		else: 	
			self.items = items
			
	def l(self) : 
		return sum([i.length() for i in items])
	
	def close(self) :
		for subitems in self.items:
			if (subitems[0].st-subitems[-1].end).l2()>10e-16 :
				subitems.append(Line(subitems[-1].end,subitems[0].st))
	
	def offset(self,r) :
		# offset each element
		self.close()
		for subitems in self.items :
			for item in subitems :
				item.offset(r)
		self.connect(r)
		
	def connect(self, r) :				
		for subitems in self.items :
			for a,b in zip(subitems, subitems[1:]) :
				i = a.intersect(b)
				for p in i : 
					draw_pointer(p.to_list())
				
						
				
						
	def clip_offset(self):
		pass	
		
	def draw(self, layer, group=None, style=styles["biarc_style"]):
		global gcodetools
		gcodetools.set_markers()

		for i in [0,1]:
			style['biarc%s_r'%i] = simplestyle.parseStyle(style['biarc%s'%i])
			style['biarc%s_r'%i]["marker-start"] = "url(#DrawCurveMarker_r)"
			del(style['biarc%s_r'%i]["marker-end"])
			style['biarc%s_r'%i] = simplestyle.formatStyle(style['biarc%s_r'%i])
		
		if group==None:
			if "preview_groups" not in dir(options.self) :
				gcodetools.preview_groups = { layer: inkex.etree.SubElement( gcodetools.layers[min(1,len(gcodetools.layers)-1)], inkex.addNS('g','svg'), {"gcodetools": "Preview group"} ) }
			elif layer not in gcodetools.preview_groups :
				gcodetools.preview_groups[layer] = inkex.etree.SubElement( gcodetools.layers[min(1,len(gcodetools.layers)-1)], inkex.addNS('g','svg'), {"gcodetools": "Preview group"} )
			group = gcodetools.preview_groups[layer]
		
		transform = gcodetools.get_transforms(group)
		if transform != [] : 
			transform = gcodetools.reverse_transform(transform)
			transform = simpletransform.formatTransform(transform)

		a,b,c = [0.,0.], [1.,0.], [0.,1.]
		k = (b[0]-a[0])*(c[1]-a[1])-(c[0]-a[0])*(b[1]-a[1])
		a,b,c = gcodetools.transform(a, layer, True), gcodetools.transform(b, layer, True), gcodetools.transform(c, layer, True)
		if ((b[0]-a[0])*(c[1]-a[1])-(c[0]-a[0])*(b[1]-a[1]))*k > 0 : reverse_angle = -1
		else : reverse_angle = 1 


		num = 0
		for subitems in self.items :
			for item in subitems :
				num += 1
				#if num>1 : break
				item.draw(group, style, layer, transform, num, reverse_angle)

	def from_old_style(self, curve) :
		#Crve defenitnion [start point, type = {'arc','line','move','end'}, arc center, arc angle, end point, [zstart, zend]]		
		self.items = []
		for sp in curve:
			print_(sp)
			if sp[1] == 'move':				
				self.items.append([])
			if sp[1] == 'arc':
				self.items[-1].append(Arc(sp[0],sp[4],sp[2],sp[3]))
			if sp[1] == 'line':
				self.items[-1].append(Line(sp[0],sp[4]))
		
			
		
			
	
################################################################################
###
### Offset function 
###
### This function offsets given cubic super path.  
### It's based on src/livarot/PathOutline.cpp from Inkscape's source code.
###
###
################################################################################
def csp_offset(csp, r) :
	offset_tolerance = 0.05
	offset_subdivision_depth = 10
	time_ = time.time()
	time_start  = time_
	print_("Offset start at %s"% time_)
	print_("Offset radius %s"% r)
	
	
	def csp_offset_segment(sp1,sp2,r) :
		result = []
		t = csp_get_t_at_curvature(sp1,sp2,1/r)
		if len(t) == 0 : t =[0.,1.]
		t.sort()
		if t[0]>.00000001 : t = [0.]+t 
		if t[-1]<.99999999 : t.append(1.) 
		for st,end in zip(t,t[1:]) :	
			c = csp_curvature_at_t(sp1,sp2,(st+end)/2)
			sp = csp_split_by_two_points(sp1,sp2,st,end)
			if sp[1]!=sp[2]:
				if (c>1/r and r<0 or c<1/r and r>0) :
					offset = offset_segment_recursion(sp[1],sp[2],r, offset_subdivision_depth, offset_tolerance) 
				else : # This part will be clipped for sure... TODO Optimize it...
					offset = offset_segment_recursion(sp[1],sp[2],r, offset_subdivision_depth, offset_tolerance) 
					
				if result==[] :
					result = offset[:]
				else: 
					if csp_subpaths_end_to_start_distance2(result,offset)<0.0001 :
						result = csp_concat_subpaths(result,offset)
					else:
						
						intersection = csp_get_subapths_last_first_intersection(result,offset)
						if intersection != [] :
							i,t1,j,t2 = intersection
							sp1_,sp2_,sp3_ = csp_split(result[i-1],result[i],t1)
							result = result[:i-1] + [ sp1_, sp2_ ]
							sp1_,sp2_,sp3_ = csp_split(offset[j-1],offset[j],t2)
							result = csp_concat_subpaths( result, [sp2_,sp3_] + offset[j+1:] )
						else : 
							pass # ???						
							#raise ValueError, "Offset curvature clipping error"
		#draw_csp([result])							
		return result					
	
						
	def create_offset_segment(sp1,sp2,r) :
		# See	Gernot Hoffmann "Bezier Curves"  p.34 -> 7.1 Bezier Offset Curves
		p0,p1,p2,p3 = P(sp1[1]),P(sp1[2]),P(sp2[0]),P(sp2[1])
		s0,s1,s3 = p1-p0,p2-p1,p3-p2
		n0 = s0.ccw().unit() if s0.l2()!=0 else P(csp_normalized_normal(sp1,sp2,0))
		n3 = s3.ccw().unit() if s3.l2()!=0 else P(csp_normalized_normal(sp1,sp2,1))
		n1 = s1.ccw().unit() if s1.l2()!=0 else (n0.unit()+n3.unit()).unit()

		q0,q3 = p0+r*n0, p3+r*n3
		c = csp_curvature_at_t(sp1,sp2,0)
		q1 = q0 + (p1-p0)*(1- (r*c if abs(c)<100 else 0) )
		c = csp_curvature_at_t(sp1,sp2,1)
		q2 = q3 + (p2-p3)*(1- (r*c if abs(c)<100 else 0) ) 

		
		return [[q0.to_list(), q0.to_list(), q1.to_list()],[q2.to_list(), q3.to_list(), q3.to_list()]]
	
	
	def csp_get_subapths_last_first_intersection(s1,s2):
		_break = False
		for i in range(1,len(s1)) :
			sp11, sp12 = s1[-i-1], s1[-i]
			for j in range(1,len(s2)) :
				sp21,sp22 = s2[j-1], s2[j] 
				intersection = csp_segments_true_intersection(sp11,sp12,sp21,sp22)
				if intersection != [] :
					_break = True
					break 
			if _break:break
		if _break :
			intersection = max(intersection)
			return [len(s1)-i,intersection[0], j,intersection[1]]
		else : 
			return []
	
		
	def csp_join_offsets(prev,next,sp1,sp2,sp1_l,sp2_l,r):
		if len(next)>1 :
			if (P(prev[-1][1])-P(next[0][1])).l2()<0.001 : 
				return prev,[],next
			intersection = csp_get_subapths_last_first_intersection(prev,next)
			if intersection != [] :
				i,t1,j,t2 = intersection
				sp1_,sp2_,sp3_ = csp_split(prev[i-1],prev[i],t1)
				sp3_,sp4_,sp5_ = csp_split(next[j-1], next[j],t2)
				return prev[:i-1] + [ sp1_, sp2_ ], [], [sp4_,sp5_] + next[j+1:] 
			
		# Offsets do not intersect... will add an arc...
		start = (P(csp_at_t(sp1_l,sp2_l,1.)) + r*P(csp_normalized_normal(sp1_l,sp2_l,1.))).to_list()
		end   = (P(csp_at_t(sp1,sp2,0.)) + r*P(csp_normalized_normal(sp1,sp2,0.))).to_list()
		arc = csp_from_arc(start, end, sp1[1], r, csp_normalized_slope(sp1_l,sp2_l,1.) )
		if arc == [] :
			return prev,[],next
		else:
			# Clip prev by arc
			if csp_subpaths_end_to_start_distance2(prev,arc)>0.00001 :
				intersection = csp_get_subapths_last_first_intersection(prev,arc)
				if intersection != [] :
					i,t1,j,t2 = intersection
					sp1_,sp2_,sp3_ = csp_split(prev[i-1],prev[i],t1)
					sp3_,sp4_,sp5_ = csp_split(arc[j-1],arc[j],t2)
					prev = prev[:i-1] + [ sp1_, sp2_ ]
					arc = [sp4_,sp5_] + arc[j+1:] 
				#else : raise ValueError, "Offset curvature clipping error"
			# Clip next by arc
			if next == [] :
				return prev,[],arc
			if csp_subpaths_end_to_start_distance2(arc,next)>0.00001 :
				intersection = csp_get_subapths_last_first_intersection(arc,next)
				if intersection != [] :
					i,t1,j,t2 = intersection
					sp1_,sp2_,sp3_ = csp_split(arc[i-1],arc[i],t1)
					sp3_,sp4_,sp5_ = csp_split(next[j-1],next[j],t2)
					arc = arc[:i-1] + [ sp1_, sp2_ ]
					next = [sp4_,sp5_] + next[j+1:] 
				#else : raise ValueError, "Offset curvature clipping error"

			return prev,arc,next
		
		
	def offset_segment_recursion(sp1,sp2,r, depth, tolerance) :
		sp1_r,sp2_r = create_offset_segment(sp1,sp2,r)
		err = max(
				csp_seg_to_point_distance(sp1_r,sp2_r, (P(csp_at_t(sp1,sp2,.25)) + P(csp_normalized_normal(sp1,sp2,.25))*r).to_list())[0], 
				csp_seg_to_point_distance(sp1_r,sp2_r, (P(csp_at_t(sp1,sp2,.50)) + P(csp_normalized_normal(sp1,sp2,.50))*r).to_list())[0],
				csp_seg_to_point_distance(sp1_r,sp2_r, (P(csp_at_t(sp1,sp2,.75)) + P(csp_normalized_normal(sp1,sp2,.75))*r).to_list())[0],
				)

		if  err>tolerance**2 and depth>0:
			#print_(csp_seg_to_point_distance(sp1_r,sp2_r, (P(csp_at_t(sp1,sp2,.25)) + P(csp_normalized_normal(sp1,sp2,.25))*r).to_list())[0], tolerance)
			if depth > offset_subdivision_depth-2 :
				t = csp_max_curvature(sp1,sp2)
				t = max(.1,min(.9 ,t))
			else :
				t = .5
			sp3,sp4,sp5 = csp_split(sp1,sp2,t)
			r1 = offset_segment_recursion(sp3,sp4,r, depth-1, tolerance)
			r2 = offset_segment_recursion(sp4,sp5,r, depth-1, tolerance)
			return r1[:-1]+ [[r1[-1][0],r1[-1][1],r2[0][2]]] + r2[1:]
		else :
			#draw_csp([[sp1_r,sp2_r]])
			#draw_pointer(sp1[1]+sp1_r[1], "#057", "line")
			#draw_pointer(sp2[1]+sp2_r[1], "#705", "line")
			return [sp1_r,sp2_r]
		

	############################################################################
	# Some small definitions
	############################################################################
	csp_len = len(csp)

	############################################################################
	# Prepare the path
	############################################################################
	# Remove all small segments (segment length < 0.001)

	for i in xrange(len(csp)) :
		for j in xrange(len(csp[i])) :
			sp = csp[i][j]
			if (P(sp[1])-P(sp[0])).mag() < 0.001 :
				csp[i][j][0] = sp[1]
			if (P(sp[2])-P(sp[0])).mag() < 0.001 :
				csp[i][j][2] = sp[1]
	for i in xrange(len(csp)) :
		for j in xrange(1,len(csp[i])) :
			if cspseglength(csp[i][j-1], csp[i][j])<0.001 : 
				csp[i] = csp[i][:j] + csp[i][j+1:]
		if cspseglength(csp[i][-1],csp[i][0])>0.001 : 
			csp[i][-1][2] = csp[i][-1][1]
			csp[i]+= [ [csp[i][0][1],csp[i][0][1],csp[i][0][1]] ]
	
	# TODO Get rid of self intersections.

	original_csp = csp[:]
	# Clip segments which has curvature>1/r. Because their offset will be selfintersecting and very nasty.
					
	print_("Offset prepared the path in %s"%(time.time()-time_))
	print_("Path length = %s"% sum([len(i)for i in csp] ) )
	time_ = time.time()

	############################################################################
	# Offset
	############################################################################
	# Create offsets for all segments in the path. And join them together inside each subpath. 		
	unclipped_offset = [[] for i in xrange(csp_len)]
	offsets_original = [[] for i in xrange(csp_len)]
	join_points = [[] for i in xrange(csp_len)]
	intersection = [[] for i in xrange(csp_len)]
	for i in xrange(csp_len) :
		subpath = csp[i]
		subpath_offset = []
		last_offset_len = 0
		for sp1,sp2 in zip(subpath, subpath[1:]) : 
			segment_offset = csp_offset_segment(sp1,sp2,r)
			if subpath_offset == [] :
				subpath_offset = segment_offset
				
				prev_l = len(subpath_offset)
			else : 
				prev, arc, next = csp_join_offsets(subpath_offset[-prev_l:],segment_offset,sp1,sp2,sp1_l,sp2_l,r)
				#draw_csp([prev],"Blue")
				#draw_csp([arc],"Magenta")
				subpath_offset = csp_concat_subpaths(subpath_offset[:-prev_l+1],prev,arc,next)
				prev_l = len(next)				
			sp1_l, sp2_l = sp1[:], sp2[:]
						
		# Join last and first offsets togother to close the curve
		
		prev, arc, next = csp_join_offsets(subpath_offset[-prev_l:], subpath_offset[:2], subpath[0], subpath[1], sp1_l,sp2_l, r)
		subpath_offset[:2] = next[:]
		subpath_offset = csp_concat_subpaths(subpath_offset[:-prev_l+1],prev,arc)
		#draw_csp([prev],"Blue")
		#draw_csp([arc],"Red")
		#draw_csp([next],"Red")

		# Collect subpath's offset and save it to unclipped offset list. 	
		unclipped_offset[i] = subpath_offset[:]	

		#for k,t in intersection[i]:
		#	draw_pointer(csp_at_t(subpath_offset[k-1], subpath_offset[k], t))
			
	#inkex.etree.SubElement( options.doc_root, inkex.addNS('path','svg'), {"d": cubicsuperpath.formatPath(unclipped_offset), "style":"fill:none;stroke:#0f0;"} )	
	print_("Offsetted path in %s"%(time.time()-time_))
	time_ = time.time()
	
	#for i in range(len(unclipped_offset)):
	#	draw_csp([unclipped_offset[i]], color = ["Green","Red","Blue"][i%3], width = .1)
	#return []
	############################################################################
	# Now to the clipping. 
	############################################################################
	# First of all find all intersection's between all segments of all offseted subpaths, including self intersections.

	#TODO define offset tolerance here
	global small_tolerance
	small_tolerance = 0.01
	summ = 0
	summ1 = 0 	 
	for subpath_i in xrange(csp_len) :
		for subpath_j in xrange(subpath_i,csp_len) :
			subpath = unclipped_offset[subpath_i]
			subpath1 = unclipped_offset[subpath_j]
			for i in xrange(1,len(subpath)) :
				# If subpath_i==subpath_j we are looking for self intersections, so 
				# we'll need search intersections only for xrange(i,len(subpath1))
				for j in ( xrange(i,len(subpath1)) if subpath_i==subpath_j else xrange(len(subpath1))) :
					if subpath_i==subpath_j and j==i :
						# Find self intersections of a segment
						sp1,sp2,sp3 = csp_split(subpath[i-1],subpath[i],.5)
						intersections = csp_segments_intersection(sp1,sp2,sp2,sp3)
						summ +=1 
						for t in intersections :
							summ1 += 1
							if not ( small(t[0]-1) and small(t[1]) ) and 0<=t[0]<=1 and 0<=t[1]<=1 :
								intersection[subpath_i] += [ [i,t[0]/2],[j,t[1]/2+.5] ]
					else :
						intersections = csp_segments_intersection(subpath[i-1],subpath[i],subpath1[j-1],subpath1[j])
						summ +=1 
						for t in intersections :
							summ1 += 1
							#TODO tolerance dependence to cpsp_length(t)
							if len(t) == 2 and 0<=t[0]<=1 and 0<=t[1]<=1 and not (
									subpath_i==subpath_j and (
									(j-i-1) % (len(subpath)-1) == 0 and small(t[0]-1) and small(t[1]) or 
									(i-j-1) % (len(subpath)-1) == 0 and small(t[1]-1) and small(t[0]) )  ) :
								intersection[subpath_i] += [ [i,t[0]] ]
								intersection[subpath_j] += [ [j,t[1]] ]	
								#draw_pointer(csp_at_t(subpath[i-1],subpath[i],t[0]),"#f00")
								#print_(t)
								#print_(i,j)
							elif len(t)==5 and t[4]=="Overlap":	
								intersection[subpath_i] += [ [i,t[0]], [i,t[1]] ]
								intersection[subpath_j] += [ [j,t[1]], [j,t[3]] ]

	print_("Intersections found in %s"%(time.time()-time_))
	print_("Examined %s segments"%(summ))
	print_("found %s intersections"%(summ1))
	time_ = time.time()
								
	########################################################################
	# Split unclipped offset by intersection points into splitted_offset
	########################################################################
	splitted_offset = []
	for i in xrange(csp_len) :
		subpath = unclipped_offset[i]
		if len(intersection[i]) > 0 :
			parts = csp_subpath_split_by_points(subpath, intersection[i])
			# Close	parts list to close path (The first and the last parts are joined together)		
			if  [1,0.] not in intersection[i] : 
				parts[0][0][0] = parts[-1][-1][0]
				parts[0] = csp_concat_subpaths(parts[-1], parts[0])
				splitted_offset += parts[:-1]
			else: 
				splitted_offset += parts[:]
		else :
			splitted_offset += [subpath[:]]
	
	#for i in range(len(splitted_offset)):
	#	draw_csp([splitted_offset[i]], color = ["Green","Red","Blue"][i%3])
	print_("Splitted in %s"%(time.time()-time_))
	time_ = time.time()

	
	########################################################################
	# Clipping
	########################################################################		
	result = []
	for subpath_i in range(len(splitted_offset)):
		clip = False
		s1 = splitted_offset[subpath_i]
		for subpath_j in range(len(splitted_offset)):
			s2 = splitted_offset[subpath_j]
			if (P(s1[0][1])-P(s2[-1][1])).l2()<0.0001 and ( (subpath_i+1) % len(splitted_offset) != subpath_j ): 
				if dot(csp_normalized_normal(s2[-2],s2[-1],1.),csp_normalized_slope(s1[0],s1[1],0.))*r<-0.0001 :
					clip = True
					break
			if (P(s2[0][1])-P(s1[-1][1])).l2()<0.0001 and ( (subpath_j+1) % len(splitted_offset) != subpath_i ):
				if dot(csp_normalized_normal(s2[0],s2[1],0.),csp_normalized_slope(s1[-2],s1[-1],1.))*r>0.0001 :
					clip = True
					break
			
		if not clip :
			result += [s1[:]]
		elif options.offset_draw_clippend_path :
			draw_csp([s1],color="Red",width=.1)
			draw_pointer( csp_at_t(s2[-2],s2[-1],1.)+
				(P(csp_at_t(s2[-2],s2[-1],1.))+ P(csp_normalized_normal(s2[-2],s2[-1],1.))*10).to_list(),"Green", "line"  )
			draw_pointer( csp_at_t(s1[0],s1[1],0.)+
				(P(csp_at_t(s1[0],s1[1],0.))+ P(csp_normalized_slope(s1[0],s1[1],0.))*10).to_list(),"Red", "line"  )
				
	# Now join all together and check closure and orientation of result
	joined_result = csp_join_subpaths(result)
	# Check if each subpath from joined_result is closed
	#draw_csp(joined_result,color="Green",width=1)

	
	for s in joined_result[:] :
		if csp_subpaths_end_to_start_distance2(s,s) > 0.001 :
			# Remove open parts
			if options.offset_draw_clippend_path:
				draw_csp([s],color="Orange",width=1)
				draw_pointer(s[0][1], comment= csp_subpaths_end_to_start_distance2(s,s))
				draw_pointer(s[-1][1], comment = csp_subpaths_end_to_start_distance2(s,s))
			joined_result.remove(s)
		else : 			
			# Remove small parts
			minx,miny,maxx,maxy = csp_true_bounds([s])
			if (minx[0]-maxx[0])**2 + (miny[1]-maxy[1])**2 < 0.1 :
				joined_result.remove(s)
	print_("Clipped and joined path in %s"%(time.time()-time_))
	time_ = time.time()
			
	########################################################################
	# Now to the Dummy cliping: remove parts from splitted offset if their 
	# centers are  closer to the original path than offset radius. 
	########################################################################		
	
	r1,r2 = ( (0.99*r)**2, (1.01*r)**2 ) if abs(r*.01)<1 else  ((abs(r)-1)**2, (abs(r)+1)**2)
	for s in joined_result[:]:
		dist = csp_to_point_distance(original_csp, s[int(len(s)/2)][1], dist_bounds = [r1,r2], tolerance = .000001)
		if not r1 < dist[0] < r2 : 
			joined_result.remove(s)
			if options.offset_draw_clippend_path:
				draw_csp([s], comment = math.sqrt(dist[0]))
				draw_pointer(csp_at_t(csp[dist[1]][dist[2]-1],csp[dist[1]][dist[2]],dist[3])+s[int(len(s)/2)][1],"blue", "line", comment = [math.sqrt(dist[0]),i,j,sp]  )

	print_("-----------------------------")
	print_("Total offset time %s"%(time.time()-time_start))
	print_()
	return joined_result
	
	
		


################################################################################
###
###		Biarc function
###
###		Calculates biarc approximation of cubic super path segment
###		splits segment if needed or approximates it with straight line
###
################################################################################
def biarc(sp1, sp2, z1, z2, depth=0):
	def biarc_split(sp1,sp2, z1, z2, depth): 
		if depth<options.biarc_max_split_depth:
			sp1,sp2,sp3 = csp_split(sp1,sp2)
			l1, l2 = cspseglength(sp1,sp2), cspseglength(sp2,sp3)
			if l1+l2 == 0 : zm = z1
			else : zm = z1+(z2-z1)*l1/(l1+l2)
			return biarc(sp1,sp2,z1,zm,depth+1)+biarc(sp2,sp3,zm,z2,depth+1)
		else: return [ [sp1[1],'line', 0, 0, sp2[1], [z1,z2]] ]

	P0, P4 = P(sp1[1]), P(sp2[1])
	TS, TE, v = (P(sp1[2])-P0), -(P(sp2[0])-P4), P0 - P4
	tsa, tea, va = TS.angle(), TE.angle(), v.angle()
	if TE.mag()<straight_distance_tolerance and TS.mag()<straight_distance_tolerance:	
		# Both tangents are zerro - line straight
		return [ [sp1[1],'line', 0, 0, sp2[1], [z1,z2]] ]
	if TE.mag() < straight_distance_tolerance:
		TE = -(TS+v).unit()
		r = TS.mag()/v.mag()*2
	elif TS.mag() < straight_distance_tolerance:
		TS = -(TE+v).unit()
		r = 1/( TE.mag()/v.mag()*2 )
	else:	
		r=TS.mag()/TE.mag()
	TS, TE = TS.unit(), TE.unit()
	tang_are_parallel = ((tsa-tea)%math.pi<straight_tolerance or math.pi-(tsa-tea)%math.pi<straight_tolerance )
	if ( tang_are_parallel  and 
				((v.mag()<straight_distance_tolerance or TE.mag()<straight_distance_tolerance or TS.mag()<straight_distance_tolerance) or
					1-abs(TS*v/(TS.mag()*v.mag()))<straight_tolerance)	):
				# Both tangents are parallel and start and end are the same - line straight
				# or one of tangents still smaller then tollerance

				# Both tangents and v are parallel - line straight
		return [ [sp1[1],'line', 0, 0, sp2[1], [z1,z2]] ]

	c,b,a = v*v, 2*v*(r*TS+TE), 2*r*(TS*TE-1)
	if v.mag()==0:
		return biarc_split(sp1, sp2, z1, z2, depth)
	asmall, bsmall, csmall = abs(a)<10**-10,abs(b)<10**-10,abs(c)<10**-10 
	if 		asmall and b!=0:	beta = -c/b
	elif 	csmall and a!=0:	beta = -b/a 
	elif not asmall:	 
		discr = b*b-4*a*c
		if discr < 0:	raise ValueError, (a,b,c,discr)
		disq = discr**.5
		beta1 = (-b - disq) / 2 / a
		beta2 = (-b + disq) / 2 / a
		if beta1*beta2 > 0 :	raise ValueError, (a,b,c,disq,beta1,beta2)
		beta = max(beta1, beta2)
	elif	asmall and bsmall:	
		return biarc_split(sp1, sp2, z1, z2, depth)
	alpha = beta * r
	ab = alpha + beta 
	P1 = P0 + alpha * TS
	P3 = P4 - beta * TE
	P2 = (beta / ab)  * P1 + (alpha / ab) * P3


	def calculate_arc_params(P0,P1,P2):
		D = (P0+P2)/2
		if (D-P1).mag()==0: return None, None
		R = D - ( (D-P0).mag()**2/(D-P1).mag() )*(P1-D).unit()
		p0a, p1a, p2a = (P0-R).angle()%(2*math.pi), (P1-R).angle()%(2*math.pi), (P2-R).angle()%(2*math.pi)
		alpha =  (p2a - p0a) % (2*math.pi)					
		if (p0a<p2a and  (p1a<p0a or p2a<p1a))	or	(p2a<p1a<p0a) : 
			alpha = -2*math.pi+alpha 
		if abs(R.x)>1000000 or abs(R.y)>1000000  or (R-P0).mag<options.min_arc_radius**2 :
			return None, None
		else :	
			return  R, alpha
	R1,a1 = calculate_arc_params(P0,P1,P2)
	R2,a2 = calculate_arc_params(P2,P3,P4)
	if R1==None or R2==None or (R1-P0).mag()<straight_tolerance or (R2-P2).mag()<straight_tolerance	: return [ [sp1[1],'line', 0, 0, sp2[1], [z1,z2]] ]
	
	d = csp_to_arc_distance(sp1,sp2, [P0,P2,R1,a1],[P2,P4,R2,a2])
	if d > options.biarc_tolerance and depth<options.biarc_max_split_depth	 : return biarc_split(sp1, sp2, z1, z2, depth)
	else:
		if R2.mag()*a2 == 0 : zm = z2
		else : zm  = z1 + (z2-z1)*(abs(R1.mag()*a1))/(abs(R2.mag()*a2)+abs(R1.mag()*a1)) 

		l = (P0-P2).l2()
		if  l < EMC_TOLERANCE_EQUAL**2 or l<EMC_TOLERANCE_EQUAL**2 * R1.l2() /100 :
			# arc should be straight otherwise it could be threated as full circle
			arc1 = [ sp1[1], 'line', 0, 0, [P2.x,P2.y], [z1,zm] ] 
		else :
			arc1 = [ sp1[1], 'arc', [R1.x,R1.y], a1, [P2.x,P2.y], [z1,zm] ] 

		l = (P4-P2).l2()
		if  l < EMC_TOLERANCE_EQUAL**2 or l<EMC_TOLERANCE_EQUAL**2 * R2.l2() /100 :
			# arc should be straight otherwise it could be threated as full circle
			arc2 = [ [P2.x,P2.y], 'line', 0, 0, [P4.x,P4.y], [zm,z2] ] 
		else :
			arc2 = [ [P2.x,P2.y], 'arc', [R2.x,R2.y], a2, [P4.x,P4.y], [zm,z2] ]
		
		return [ arc1, arc2 ]


def biarc_curve_segment_length(seg):
	if seg[1] == "arc" :
		return math.sqrt((seg[0][0]-seg[2][0])**2+(seg[0][1]-seg[2][1])**2)*seg[3]
	elif seg[1] == "line" :	
		return math.sqrt((seg[0][0]-seg[4][0])**2+(seg[0][1]-seg[4][1])**2)
	else: 
		return 0	


def biarc_curve_clip_at_l(curve, l, clip_type = "strict") :
	# get first subcurve and ceck it's length  
	subcurve, subcurve_l, moved = [], 0, False
	for seg in curve:
		if seg[1] == "move" and moved or seg[1] == "end" :	
			break
		if seg[1] == "move" : moved = True 
		subcurve_l += biarc_curve_segment_length(seg)
		if seg[1] == "arc" or seg[1] == "line" : 
			subcurve += [seg]

	if subcurve_l < l and clip_type == "strict" : return []	
	lc = 0
	if (subcurve[-1][4][0]-subcurve[0][0][0])**2 + (subcurve[-1][4][1]-subcurve[0][0][1])**2 < 10**-7 : subcurve_closed = True
	i = 0
	reverse = False
	while lc<l :
		seg = subcurve[i]
		if reverse :  
			if seg[1] == "line" :
				seg = [seg[4], "line", 0 , 0, seg[0], seg[5]] # Hmmm... Do we have to swap seg[5][0] and seg[5][1] (zstart and zend) or not?
			elif seg[1] == "arc" :
				seg = [seg[4], "arc", seg[2] , -seg[3], seg[0], seg[5]] # Hmmm... Do we have to swap seg[5][0] and seg[5][1] (zstart and zend) or not?
		ls = biarc_curve_segment_length(seg)
		if ls != 0 :
			if l-lc>ls :
				res += [seg]
			else :
				if seg[1] == "arc" :
					r  = math.sqrt((seg[0][0]-seg[2][0])**2+(seg[0][1]-seg[2][1])**2)
					x,y = seg[0][0]-seg[2][0], seg[0][1]-seg[2][1]
					a = seg[3]/ls*(l-lc)
					x,y = x*math.cos(a) - y*math.sin(a),  x*math.sin(a) + y*math.cos(a)
					x,y = x+seg[2][0], y+seg[2][1]
					res += [[ seg[0], "arc",  seg[2], a, [x,y], [seg[5][0],seg[5][1]/ls*(l-lc)]  ]]
				if seg[1] == "line" :
					res += [[ seg[0], "line",  0, 0, [(seg[4][0]-seg[0][0])/ls*(l-lc),(seg[4][1]-seg[0][1])/ls*(l-lc)], [seg[5][0],seg[5][1]/ls*(l-lc)]  ]]
		i += 1 
		if i >= len(subcurve) and not subcurve_closed: 
			reverse = not reverse
		i = i%len(subcurve)
	return res	

	
	
class Postprocessor():
	def __init__(self, error_function_handler):	
		self.error = error_function_handler 
		self.functions = {
					"remap"		: self.remap,
					"remapi"	: self.remapi ,
					"scale"		: self.scale,
					"move"		: self.move,
					"flip"		: self.flip_axis,
					"flip_axis"	: self.flip_axis,
					"round"		: self.round_coordinates,
					"parameterize"	: self.parameterize,
					"regex"			: self.re_sub_on_gcode_lines
					}
	
			
	def process(self,command):
		command = re.sub(r"\\\\",":#:#:slash:#:#:",command)
		command = re.sub(r"\\;",":#:#:semicolon:#:#:",command)
		command = command.split(";")
		for s in command: 
			s = re.sub(":#:#:slash:#:#:","\\\\",s)
			s = re.sub(":#:#:semicolon:#:#:","\\;",s)
			s = s.strip()
			if s!="" :
				self.parse_command(s)		
			
	
	def parse_command(self,command):
		r = re.match(r"([A-Za-z0-9_]+)\s*\(\s*(.*)\)",command)
		if not r:
			self.error("Parse error while postprocessing.\n(Command: '%s')"%(command), "error")
		function, parameters = r.group(1).lower(),r.group(2)
		if function in self.functions :
			print_("Postprocessor: executing function %s(%s)"%(function,parameters))
			self.functions[function](parameters)
		else : 
			self.error("Unrecognized function '%s' while postprocessing.\n(Command: '%s')"%(function,command), "error")
	
	
	def re_sub_on_gcode_lines(self, parameters):
		gcode = self.gcode.split("\n")
		self.gcode = ""
		try :
			for line in gcode :
				self.gcode += eval( "re.sub(%s,line)"%parameters) +"\n"

		except Exception as ex :	
			self.error("Bad parameters for regexp. They should be as re.sub pattern and replacement parameters! For example: r\"G0(\d)\", r\"G\\1\" \n(Parameters: '%s')\n %s"%(parameters, ex), "error")				
		
	
	def remapi(self,parameters):
		self.remap(parameters, case_sensitive = True)
	
	
	def remap(self,parameters, case_sensitive = False):
		# remap parameters should be like "x->y,y->x"
		parameters = parameters.replace("\,",":#:#:coma:#:#:")
		parameters = parameters.split(",")
		pattern, remap = [], []
		for s in parameters:
			s = s.replace(":#:#:coma:#:#:","\,")
			r = re.match("""\s*(\'|\")(.*)\\1\s*->\s*(\'|\")(.*)\\3\s*""",s)
			if not r :
				self.error("Bad parameters for remap.\n(Parameters: '%s')"%(parameters), "error")
			pattern +=[r.group(2)]	
			remap +=[r.group(4)]	
		
		
		
		for i in range(len(pattern)) :
			if case_sensitive :
				self.gcode = ireplace(self.gcode, pattern[i], ":#:#:remap_pattern%s:#:#:"%i )
			else :
				self.gcode = self.gcode.replace(pattern[i], ":#:#:remap_pattern%s:#:#:"%i)
			
		for i in range(len(remap)) :
			self.gcode = self.gcode.replace(":#:#:remap_pattern%s:#:#:"%i, remap[i])
	
	
	def transform(self, move, scale):
		axis = ["xi","yj","zk","a"]
		flip = scale[0]*scale[1]*scale[2] < 0 
		gcode = ""
		warned = []
		r_scale = scale[0]
		plane = "g17"
		for s in self.gcode.split("\n"):
			# get plane selection: 
			s_wo_comments = re.sub(r"\([^\)]*\)","",s)
			r = re.search(r"(?i)(G17|G18|G19)", s_wo_comments)
			if r :
				plane = r.group(1).lower()
				if plane == "g17" : r_scale = scale[0] # plane XY -> scale x
				if plane == "g18" : r_scale = scale[0] # plane XZ -> scale x
				if plane == "g19" : r_scale = scale[1] # plane YZ -> scale y
			# Raise warning if scale factors are not the game for G02 and G03	
			if plane not in warned:
				r = re.search(r"(?i)(G02|G03)", s_wo_comments)
				if r :
					if plane == "g17" and scale[0]!=scale[1]: self.error("Post-processor: Scale factors for X and Y axis are not the same. G02 and G03 codes will be corrupted.","warning") 
					if plane == "g18" and scale[0]!=scale[2]: self.error("Post-processor: Scale factors for X and Z axis are not the same. G02 and G03 codes will be corrupted.","warning") 
					if plane == "g19" and scale[1]!=scale[2]: self.error("Post-processor: Scale factors for Y and Z axis are not the same. G02 and G03 codes will be corrupted.","warning") 
					warned += [plane]
			# Transform		
			for i in range(len(axis)) :
				if move[i] != 0 or scale[i] != 1:
					for a in axis[i] :
						r = re.search(r"(?i)("+a+r")\s*(-?)\s*(\d*\.?\d*)", s)
						if r and r.group(3)!="":
							s = re.sub(r"(?i)("+a+r")\s*(-?)\s*(\d*\.?\d*)", r"\1 %f"%(float(r.group(2)+r.group(3))*scale[i]+(move[i] if a not in ["i","j","k"] else 0) ), s)
			#scale radius R
			if r_scale != 1 :
				r = re.search(r"(?i)(r)\s*(-?\s*(\d*\.?\d*))", s)
				if r and r.group(3)!="":
					try:
						s = re.sub(r"(?i)(r)\s*(-?)\s*(\d*\.?\d*)", r"\1 %f"%( float(r.group(2)+r.group(3))*r_scale ), s)
					except:
						pass	

			gcode += s + "\n"
			
		self.gcode = gcode
		if flip : 
			self.remapi("'G02'->'G03', 'G03'->'G02'")


	def parameterize(self,parameters) :
		planes = []
		feeds = {}
		coords = []
		gcode = ""
		coords_def = {"x":"x","y":"y","z":"z","i":"x","j":"y","k":"z","a":"a"}
		for s in self.gcode.split("\n"):
			s_wo_comments = re.sub(r"\([^\)]*\)","",s)
			# get Planes
			r = re.search(r"(?i)(G17|G18|G19)", s_wo_comments)
			if r :
				plane = r.group(1).lower()
				if plane not in planes : 
					planes += [plane]
			# get Feeds
			r = re.search(r"(?i)(F)\s*(-?)\s*(\d*\.?\d*)", s_wo_comments)
			if r :
				feed  = float (r.group(2)+r.group(3))
				if feed not in feeds :
					feeds[feed] = "#"+str(len(feeds)+20)
					
			#Coordinates
			for c in "xyzijka" :
				r = re.search(r"(?i)("+c+r")\s*(-?)\s*(\d*\.?\d*)", s_wo_comments)
				if r :
					c = coords_def[r.group(1).lower()]
					if c not in coords :
						coords += [c]
		# Add offset parametrization
		offset = {"x":"#6","y":"#7","z":"#8","a":"#9"}
		for c in coords:
			gcode += "%s  = 0 (%s axis offset)\n" %  (offset[c],c.upper())
			
		# Add scale parametrization
		if planes == [] : planes = ["g17"]
		if len(planes)>1 :  # have G02 and G03 in several planes scale_x = scale_y = scale_z required
			gcode += "#10 = 1 (Scale factor)\n"
			scale = {"x":"#10","i":"#10","y":"#10","j":"#10","z":"#10","k":"#10","r":"#10"}
		else :
			gcode += "#10 = 1 (%s Scale factor)\n" % ({"g17":"XY","g18":"XZ","g19":"YZ"}[planes[0]])
			gcode += "#11 = 1 (%s Scale factor)\n" % ({"g17":"Z","g18":"Y","g19":"X"}[planes[0]])
			scale = {"x":"#10","i":"#10","y":"#10","j":"#10","z":"#10","k":"#10","r":"#10"}
			if "g17" in planes :
				scale["z"] = "#11"				
				scale["k"] = "#11"				
			if "g18" in planes :
				scale["y"] = "#11"				
				scale["j"] = "#11"				
			if "g19" in planes :
				scale["x"] = "#11"				
				scale["i"] = "#11"				
		# Add a scale 
		if "a" in coords:
			gcode += "#12  = 1 (A axis scale)\n" 
			scale["a"] = "#12"
		
		# Add feed parametrization 
		for f in feeds :
			gcode += "%s = %f (Feed definition)\n" % (feeds[f],f)

		# Parameterize Gcode		
		for s in self.gcode.split("\n"):
			#feed replace :
			r = re.search(r"(?i)(F)\s*(-?)\s*(\d*\.?\d*)", s)
			if r and len(r.group(3))>0:
				s = re.sub(r"(?i)(F)\s*(-?)\s*(\d*\.?\d*)", "F [%s]"%feeds[float(r.group(2)+r.group(3))], s)
			#Coords XYZA replace
			for c in "xyza" :
				r = re.search(r"(?i)(("+c+r")\s*(-?)\s*(\d*\.?\d*))", s)
				if r and len(r.group(4))>0:
					s = re.sub(r"(?i)("+c+r")\s*((-?)\s*(\d*\.?\d*))", r"\1[\2*%s+%s]"%(scale[c],offset[c]), s)

			#Coords IJKR replace
			for c in "ijkr" :
				r = re.search(r"(?i)(("+c+r")\s*(-?)\s*(\d*\.?\d*))", s)
				if r and len(r.group(4))>0:
					s = re.sub(r"(?i)("+c+r")\s*((-?)\s*(\d*\.?\d*))", r"\1[\2*%s]"%scale[c], s)

			gcode += s + "\n"
	
		self.gcode = gcode	

	
	def round_coordinates(self,parameters) :
		try: 
			round_ = int(parameters)
		except :	
			self.error("Bad parameters for round. Round should be an integer! \n(Parameters: '%s')"%(parameters), "error")		
		gcode = ""
		for s in self.gcode.split("\n"):
			for a in "xyzijkaf" :
				r = re.search(r"(?i)("+a+r")\s*(-?\s*(\d*\.?\d*))", s)
				if r : 
					
					if r.group(2)!="":
						s = re.sub(
									r"(?i)("+a+r")\s*(-?)\s*(\d*\.?\d*)", 
									(r"\1 %0."+str(round_)+"f" if round_>0 else r"\1 %d")%round(float(r.group(2)),round_),
									s)
			gcode += s + "\n"
		self.gcode = gcode
	

	def scale(self, parameters):
		parameters = parameters.split(",")
		scale = [1.,1.,1.,1.]
		try :
			for i in range(len(parameters)) :
				if float(parameters[i])==0 : 
					self.error("Bad parameters for scale. Scale should not be 0 at any axis! \n(Parameters: '%s')"%(parameters), "error")		
				scale[i] = float(parameters[i])
		except :
			self.error("Bad parameters for scale.\n(Parameters: '%s')"%(parameters), "error")
		self.transform([0,0,0,0],scale)		

	
	def move(self, parameters):
		parameters = parameters.split(",")
		move = [0.,0.,0.,0.]
		try :
			for i in range(len(parameters)) :
				move[i] = float(parameters[i])
		except :
			self.error("Bad parameters for move.\n(Parameters: '%s')"%(parameters), "error")
		self.transform(move,[1.,1.,1.,1.])		


	def flip_axis(self, parameters):
		parameters = parameters.lower()
		axis = {"x":1.,"y":1.,"z":1.,"a":1.}	
		for p in parameters: 
			if p in [","," ","	","\r","'",'"'] : continue
			if p not in ["x","y","z","a"] : 
				self.error("Bad parameters for flip_axis. Parameter should be string consists of 'xyza' \n(Parameters: '%s')"%(parameters), "error")
			axis[p] = -axis[p]
		self.scale("%f,%f,%f,%f"%(axis["x"],axis["y"],axis["z"],axis["a"]))	

	
			
################################################################################
###		Polygon class
################################################################################
class Polygon:
	def __init__(self, polygon=None):
		self.polygon = [] if polygon==None else polygon[:]
	
	
	def move(self, x, y) :
		for i in range(len(self.polygon)) :
			for j in range(len(self.polygon[i])) :
				self.polygon[i][j][0] += x
				self.polygon[i][j][1] += y
	
	
	def bounds(self) : 
		minx,miny,maxx,maxy = 1e400, 1e400, -1e400, -1e400
		for poly in self.polygon :
			for p in poly :
				if minx > p[0] : minx = p[0]
				if miny > p[1] : miny = p[1]
				if maxx < p[0] : maxx = p[0]
				if maxy < p[1] : maxy = p[1]
		return minx*1,miny*1,maxx*1,maxy*1		
	
	
	def width(self):
		b = self.bounds()
		return b[2]-b[0]
	
	
	def rotate_(self,sin,cos) :
		self.polygon = [
				[
					[point[0]*cos - point[1]*sin,point[0]*sin + point[1]*cos] for point in subpoly
				]			
				for subpoly in self.polygon
			]

	
	def rotate(self, a):
		cos, sin = math.cos(a), math.sin(a)
		self.rotate_(sin,cos)
	
			
	def drop_into_direction(self, direction, surface) :
		# Polygon is a list of simple polygons
		# Surface is a polygon + line y = 0 
		# Direction is [dx,dy]  
		if len(self.polygon) == 0 or len(self.polygon[0])==0 : return
		if direction[0]**2 + direction[1]**2 <1e-10 : return
		direction = normalize(direction)
		sin,cos = direction[0], -direction[1]
		self.rotate_(-sin,cos)
		surface.rotate_(-sin,cos)
		self.drop_down(surface, zerro_plane = False)
		self.rotate_(sin,cos)
		surface.rotate_(sin,cos)
		
			
	def centroid(self):
		centroids = []
		sa = 0
		for poly in self.polygon:
			cx,cy,a = 0,0,0
			for i in range(len(poly)):
				[x1,y1],[x2,y2] = poly[i-1],poly[i]
				cx += (x1+x2)*(x1*y2-x2*y1)
				cy += (y1+y2)*(x1*y2-x2*y1)
				a  += (x1*y2-x2*y1)
			a *= 3.
			if abs(a)>0 :
				cx /= a
				cy /= a
				sa += abs(a)
				centroids += [ [cx,cy,a] ]
		if sa == 0 : return	[0.,0.]
		cx,cy = 0.,0.
		for c in centroids :
			cx += c[0]*c[2]
			cy += c[1]*c[2]
		cx /= sa
		cy /= sa
		return [cx,cy]

			
	def drop_down(self, surface, zerro_plane = True) :
		# Polygon is a list of simple polygons
		# Surface is a polygon + line y = 0 
		# Down means min y (0,-1)  
		if len(self.polygon) == 0 or len(self.polygon[0])==0 : return
		# Get surface top point
		top = surface.bounds()[3]
		if zerro_plane : top = max(0, top)
		# Get polygon bottom point
		bottom = self.bounds()[1]
		self.move(0, top - bottom + 10)		
		# Now get shortest distance from surface to polygon in positive x=0 direction
		# Such distance = min(distance(vertex, edge)...)  where edge from surface and 
		# vertex from polygon and vice versa...
		dist = 1e300
		for poly in surface.polygon :
			for i in range(len(poly)) :
				for poly1 in self.polygon :
					for i1 in range(len(poly1)) :
						st,end = poly[i-1], poly[i] 
						vertex = poly1[i1]
						if st[0]<=vertex[0]<= end[0] or end[0]<=vertex[0]<=st[0] :
							if st[0]==end[0] : d = min(vertex[1]-st[1],vertex[1]-end[1])
							else : d = vertex[1] - st[1] - (end[1]-st[1])*(vertex[0]-st[0])/(end[0]-st[0]) 
							if dist > d  : dist = d
						# and vice versa just change the sign because vertex now under the edge
						st,end = poly1[i1-1], poly1[i1] 
						vertex = poly[i]
						if st[0]<=vertex[0]<=end[0] or end[0]<=vertex[0]<=st[0] :
							if st[0]==end[0] : d = min(- vertex[1]+st[1],-vertex[1]+end[1])
							else : d =  - vertex[1] + st[1] + (end[1]-st[1])*(vertex[0]-st[0])/(end[0]-st[0]) 
							if dist > d  : dist = d
		
		if zerro_plane and dist > 10 + top : dist = 10 + top 
		#print_(dist, top, bottom)
		#self.draw()
		self.move(0, -dist)		
		
					
	def draw(self,color="#075",width=.1, group = None) :
		csp = [csp_subpath_line_to([],poly+[poly[0]]) for poly in self.polygon]
		draw_csp( csp, color=color,width=width, group = group)
			
			
	
	def add(self, add) :
		if type(add) == type([]) :
			self.polygon += add[:]
		else :	
			self.polygon += add.polygon[:]

	
	def point_inside(self,p) :
		inside = False
		for poly in self.polygon :
			for i in range(len(poly)):
				st,end = poly[i-1], poly[i]
				if p==st or p==end : return True # point is a vertex = point is on the edge
				if st[0]>end[0] : st, end = end, st # This will be needed to check that edge if open only at rigth end
				c = (p[1]-st[1])*(end[0]-st[0])-(end[1]-st[1])*(p[0]-st[0])
				#print_(c)
				if st[0]<=p[0]<end[0] : 
					if c<0 : 
						inside = not inside
					elif c == 0 : return True # point is on the edge
				elif st[0]==end[0]==p[0] and (st[1]<=p[1]<=end[1] or end[1]<=p[1]<=st[1]) : # point is on the edge
					return True
		return inside			

	
	def hull(self) :
		# Add vertices at all self intersection points. 
		hull = []
		for i1 in range(len(self.polygon)):
			poly1 = self.polygon[i1]
			poly_ = []
			for j1 in range(len(poly1)):
				s, e = poly1[j1-1],poly1[j1]
				poly_ += [s]
				
				# Check self intersections 
				for j2 in range(j1+1,len(poly1)):
					s1, e1 = poly1[j2-1],poly1[j2]
					int_ = line_line_intersection_points(s,e,s1,e1)
					for p in int_ :
						if point_to_point_d2(p,s)>0.000001 and point_to_point_d2(p,e)>0.000001 : 
							poly_ += [p]
				# Check self intersections with other polys  
				for i2 in range(len(self.polygon)):
					if i1==i2 : continue
					poly2 = self.polygon[i2]
					for j2 in range(len(poly2)):
						s1, e1 = poly2[j2-1],poly2[j2]
						int_ = line_line_intersection_points(s,e,s1,e1)
						for p in int_ :
							if point_to_point_d2(p,s)>0.000001 and point_to_point_d2(p,e)>0.000001 : 
								poly_ += [p]
			hull += [poly_]
		# Create the dictionary containing all edges in both directions
		edges = {}
		for poly in self.polygon :
			for i in range(len(poly)):
				s,e = tuple(poly[i-1]), tuple(poly[i])
				if (point_to_point_d2(e,s)<0.000001) : continue
				break_s, break_e = False, False
				for p in edges :
					if point_to_point_d2(p,s)<0.000001 : 
						break_s = True
						s = p
					if point_to_point_d2(p,e)<0.000001 : 
						break_e = True
						e = p
					if break_s and break_e : break
				l = point_to_point_d(s,e)
				if not break_s and not break_e : 
					edges[s] = [ [s,e,l] ]
					edges[e] = [ [e,s,l] ]
					#draw_pointer(s+e,"red","line")
					#draw_pointer(s+e,"red","line")
				else : 
					if e in edges :	
						for edge in edges[e] :	
							if point_to_point_d2(edge[1],s)<0.000001 :
								break
						if point_to_point_d2(edge[1],s)>0.000001 :
							edges[e] += [ [e,s,l] ]
							#draw_pointer(s+e,"red","line")
							
					else : 
						edges[e] = [ [e,s,l] ]
						#draw_pointer(s+e,"green","line")
					if s in edges :	
						for edge in edges[s] :	
							if  point_to_point_d2(edge[1],e)<0.000001 :
								break
						if point_to_point_d2(edge[1],e)>0.000001 :
							edges[s] += [ [s,e, l] ]
							#draw_pointer(s+e,"red","line")
					else : 
						edges[s] = [ [s,e,l] ]
						#draw_pointer(s+e,"green","line")

		
		def angle_quadrant(sin,cos):
			# quadrants are (0,pi/2], (pi/2,pi], (pi,3*pi/2], (3*pi/2, 2*pi], i.e. 0 is in the 4-th quadrant
			if sin>0 and cos>=0 : return 1
			if sin>=0 and cos<0 : return 2
			if sin<0 and cos<=0 : return 3
			if sin<=0 and cos>0 : return 4
			
		
		def angle_is_less(sin,cos,sin1,cos1):
			# 0 = 2*pi is the largest angle
			if [sin1, cos1] == [0,1] : return True
			if [sin, cos] == [0,1] : return False
			if angle_quadrant(sin,cos)>angle_quadrant(sin1,cos1) : 
				return False
			if angle_quadrant(sin,cos)<angle_quadrant(sin1,cos1) : 
				return True
			if sin>=0 and cos>0 : return sin<sin1
			if sin>0 and cos<=0 : return sin>sin1
			if sin<=0 and cos<0 : return sin>sin1
			if sin<0 and cos>=0 : return sin<sin1

			
		def get_closes_edge_by_angle(edges, last):
			# Last edge is normalized vector of the last edge.
			min_angle = [0,1]
			next = last
			last_edge = [(last[0][0]-last[1][0])/last[2], (last[0][1]-last[1][1])/last[2]]
			for p in edges:
				#draw_pointer(list(p[0])+[p[0][0]+last_edge[0]*40,p[0][1]+last_edge[1]*40], "Red", "line", width=1)
				#print_("len(edges)=",len(edges))
				cur = [(p[1][0]-p[0][0])/p[2],(p[1][1]-p[0][1])/p[2]]
				cos, sin = dot(cur,last_edge),  cross(cur,last_edge)
				#draw_pointer(list(p[0])+[p[0][0]+cur[0]*40,p[0][1]+cur[1]*40], "Orange", "line", width=1, comment = [sin,cos])
				#print_("cos, sin=",cos,sin)
				#print_("min_angle_before=",min_angle)

				if 	angle_is_less(sin,cos,min_angle[0],min_angle[1]) : 
					min_angle = [sin,cos]
					next = p
				#print_("min_angle=",min_angle)

			return next		
			
		# Join edges together into new polygon cutting the vertexes inside new polygon
		self.polygon = []
		len_edges = sum([len(edges[p]) for p in edges]) 
		loops = 0 
		
		while len(edges)>0 :
			poly = []
			if loops > len_edges  : raise ValueError, "Hull error"
			loops+=1
			# Find left most vertex.
			start = (1e100,1)
			for edge in edges : 
				start = min(start, min(edges[edge])) 
			last = [(start[0][0]-1,start[0][1]),start[0],1]
			first_run = True
			loops1 = 0
			while (last[1]!=start[0] or first_run) : 	
				first_run = False
				if loops1 > len_edges  : raise ValueError, "Hull error"
				loops1 += 1
				next = get_closes_edge_by_angle(edges[last[1]],last)
				#draw_pointer(next[0]+next[1],"Green","line", comment=i, width= 1)
				#print_(next[0],"-",next[1]) 

				last = next
				poly += [ list(last[0]) ]				
			self.polygon += [ poly ]
			# Remove all edges that are intersects new poly (any vertex inside new poly)
			poly_ = Polygon([poly])
			for p in edges.keys()[:] : 
				if poly_.point_inside(list(p)) : del edges[p]
		self.draw(color="Green", width=1)	


class Arangement_Genetic:
	# gene = [fittness, order, rotation, xposition]
	# spieces = [gene]*shapes count
	# population = [spieces]
	def __init__(self, polygons, material_width):
		self.population = []
		self.genes_count = len(polygons)
		self.polygons = polygons
		self.width = material_width
		self.mutation_factor = 0.1
		self.order_mutate_factor = 1.
		self.move_mutate_factor = 1.

	
	def add_random_species(self,count):
		for i in range(count):
			specimen = []
			order = range(self.genes_count)
			random.shuffle(order)
			for j in order:
				specimen += [ [j, random.random(), random.random()] ]
			self.population += [ [None,specimen] ]

	
	def species_distance2(self,sp1,sp2) :
		# retun distance, each component is normalized
		s = 0
		for j in range(self.genes_count) :
			s += ((sp1[j][0]-sp2[j][0])/self.genes_count)**2 + (( sp1[j][1]-sp2[j][1]))**2 + ((sp1[j][2]-sp2[j][2]))**2
		return s

	
	def similarity(self,sp1,top) :
		# Define similarity as a simple distance between two points in len(gene)*len(spiece) -th dimentions
		# for sp2 in top_spieces sum(|sp1-sp2|)/top_count
		sim = 0
		for sp2 in top : 
			sim += math.sqrt(species_distance2(sp1,sp2[1]))
		return sim/len(top)
		
	
	def leave_top_species(self,count):
		self.population.sort()
		res = [  copy.deepcopy(self.population[0]) ]
		del self.population[0]
		for i in range(count-1) :
			t = []
			for j in range(20) : 
				i1 = random.randint(0,len(self.population)-1) 
				t += [ [self.population[i1][0],i1] ] 
			t.sort()
			res += [  copy.deepcopy(self.population[t[0][1]]) ]
			del self.population[t[0][1]]
		self.population = res		
		#del self.population[0]
		#for c in range(count-1) :
		#	rank = []
		#	for i in range(len(self.population)) :	
		#		sim = self.similarity(self.population[i][1],res)
		#		rank += [ [self.population[i][0] / sim if sim>0 else 1e100,i] ]
		#	rank.sort()
		#	res += [  copy.deepcopy(self.population[rank[0][1]]) ]
		#	print_(rank[0],self.population[rank[0][1]][0])
		#	print_(res[-1])
		#	del self.population[rank[0][1]]
			
		self.population = res
			
			
	def populate_species(self,count, parent_count):
		self.population.sort()
		self.inc = 0
		for c in range(count):
			parent1 = random.randint(0,parent_count-1)
			parent2 = random.randint(0,parent_count-1)
			if parent1==parent2 : parent2 = (parent2+1) % parent_count
			parent1, parent2 = self.population[parent1][1], self.population[parent2][1]
			i1,i2 = 0, 0
			genes_order = []
			specimen = [ [0,0.,0.] for i in range(self.genes_count) ]
			
			self.incest_mutation_multiplyer = 1.
			self.incest_mutation_count_multiplyer = 1.

			if self.species_distance2(parent1, parent2) <= .01/self.genes_count :
				# OMG it's a incest :O!!!
				# Damn you bastards!
				self.inc +=1
				self.incest_mutation_multiplyer = 2. 
				self.incest_mutation_count_multiplyer = 2. 
			else :
				pass
#				if random.random()<.01 : print_(self.species_distance2(parent1, parent2))	
			start_gene = random.randint(0,self.genes_count)
			end_gene = (max(1,random.randint(0,self.genes_count),int(self.genes_count/4))+start_gene) % self.genes_count
			if end_gene<start_gene : 
				end_gene, start_gene = start_gene, end_gene
				parent1, parent2 = parent2, parent1
			for i in range(start_gene,end_gene) : 
				#rotation_mutate_param = random.random()/100
				#xposition_mutate_param = random.random()/100
				tr = 1. #- rotation_mutate_param
				tp = 1. #- xposition_mutate_param
				specimen[i] = [parent1[i][0], parent1[i][1]*tr+parent2[i][1]*(1-tr),parent1[i][2]*tp+parent2[i][2]*(1-tp)]
				genes_order += [ parent1[i][0] ]

			for i in range(0,start_gene)+range(end_gene,self.genes_count) : 
				tr = 0. #rotation_mutate_param
				tp = 0. #xposition_mutate_param
				j = i 
				while parent2[j][0] in genes_order :
					j = (j+1)%self.genes_count
				specimen[i] = [parent2[j][0], parent1[i][1]*tr+parent2[i][1]*(1-tr),parent1[i][2]*tp+parent2[i][2]*(1-tp)]
				genes_order += [ parent2[j][0] ]						
				

			for i in range(random.randint(self.mutation_genes_count[0],self.mutation_genes_count[0]*self.incest_mutation_count_multiplyer )) :
				if random.random() < self.order_mutate_factor * self.incest_mutation_multiplyer : 
					i1,i2 = random.randint(0,self.genes_count-1),random.randint(0,self.genes_count-1)
					specimen[i1][0], specimen[i2][0] = specimen[i2][0], specimen[i1][0]
				if random.random() < self.move_mutation_factor * self.incest_mutation_multiplyer: 
					i1 = random.randint(0,self.genes_count-1)
					specimen[i1][1] =  (specimen[i1][1]+random.random()*math.pi2*self.move_mutation_multiplier)%1.
					specimen[i1][2] =  (specimen[i1][2]+random.random()*self.move_mutation_multiplier)%1.
			self.population += [ [None,specimen] ]	

	
	def test_spiece_drop_down(self,spiece) : 
		surface = Polygon()
		for p in spiece :
			time_ = time.time()
			poly = Polygon(copy.deepcopy(self.polygons[p[0]].polygon))
			poly.rotate(p[1]*math.pi2)
			w = poly.width()
			left = poly.bounds()[0]
			poly.move( -left + (self.width-w)*p[2],0)
			poly.drop_down(surface)
			surface.add(poly)
		return surface

	
	def test(self,test_function): 
		time_ = time.time()
		for i in range(len(self.population)) :
			if self.population[i][0] == None :
				surface = test_function(self.population[i][1])
				b = surface.bounds()
				self.population[i][0] = (b[3]-b[1])*(b[2]-b[0])
		self.population.sort() 				

	def test_spiece_centroid(self,spiece) : 
		poly = Polygon(	self.polygons[spiece[0][0]].polygon[:])
		poly.rotate(spiece[0][1]*math.pi2)
		surface  = Polygon(poly.polygon)
		for p in spiece[1:] :
			poly = Polygon(self.polygons[p[0]].polygon[:])
			c = surface.centroid()
			surface.move(-c[0],-c[1])
			c1 = poly.centroid()
			poly.move(-c1[0],-c1[1])
			poly.rotate(p[1]*math.pi2+p[2]*math.pi2)
			surface.rotate(p[2]*math.pi2)
			poly.drop_down(surface)
			surface.add(poly)
			surface.rotate(-p[2]*math.pi2)
		return surface
		
				
	def test_inline(self) : 
		###
		###	Fast test function using weave's from scipy inline function
		###
		try :
			converters is None 
		except :	
			try:
				from scipy import weave
				from scipy.weave import converters
			except:
				options.self.error("For this function Scipy is needed. See http://www.cnc-club.ru/gcodetools for details.","error")		
	
		# Prepare vars 
		poly_, subpoly_, points_ = [], [], []
		for  poly in self.polygons :
			p = poly.polygon
			poly_ += [len(subpoly_), len(subpoly_)+len(p)*2]
			for subpoly in p :
				subpoly_ += [len(points_), len(points_)+len(subpoly)*2+2]
				for point in subpoly :
					points_ += point
				points_ += subpoly[0] # Close subpolygon

		test_ = []
		population_ = []
		for spiece in self.population:
			test_.append( spiece[0] if spiece[0] != None else -1)
			for sp in spiece[1]:
				population_ += sp
			
		lp_, ls_, l_, lt_ = len(poly_), len(subpoly_), len(points_), len(test_)
		 
		f = open('inline_test.c', 'r')
		code = f.read()
		f.close()
		
		f = open('inline_test_functions.c', 'r')
		functions = f.read()
		f.close()
		
		stdout_ = sys.stdout
		s = ''		
		sys.stdout = s 

		test = weave.inline(
							code,
							['points_','subpoly_','poly_', 'lp_', 'ls_', 'l_', 'lt_','test_', 'population_'],
							compiler='gcc',
							support_code = functions,
							)
		if s!='' : options.self.error(s,"warning")		
		sys.stdout = stdout_
		
		for i in range(len(test_)):
			self.population[i][0] = test_[i]
		
		
		
		
		#surface.draw()

		
################################################################################
###
###		Gcodetools class
###
################################################################################

class Gcodetools(inkex.Effect):

	def export_gcode(self,gcode, no_headers = False,comments = '') :
		if self.options.postprocessor != ""  or self.options.postprocessor_custom != "" :
			postprocessor = Postprocessor(self.error)
			postprocessor.gcode = gcode
			if self.options.postprocessor != "" :
				postprocessor.process(self.options.postprocessor)
			if self.options.postprocessor_custom != "" :
				postprocessor.process(self.options.postprocessor_custom)

		if not no_headers :
			postprocessor.gcode = self.header + postprocessor.gcode + self.footer
			
		if comments == ';' :
			postprocessor.gcode = gcode_comments(postprocessor.gcode)
		
		f = open(self.options.directory+self.options.file, "w")	
		f.write(postprocessor.gcode)
		f.close()							


################################################################################
###		In/out paths:
###		TODO move it to the bottom
################################################################################
	def plasma_prepare_path(self) :
	
		def add_arc(sp1,sp2,end = False,l=10.,r=10.) :
			if not end :
				n = csp_normalized_normal(sp1,sp2,0.)
				return csp_reverse([arc_from_s_r_n_l(sp1[1],r,n,-l)])[0]
			else: 
				n = csp_normalized_normal(sp1,sp2,1.)
				return arc_from_s_r_n_l(sp2[1],r,n,l)
				
		def add_normal(sp1,sp2,end = False,l=10.,r=10.) :
			# r is needed only for be compatible with add_arc
			if not end : 
				n = csp_normalized_normal(sp1,sp2,0.)
				p = [n[0]*l+sp1[1][0],n[1]*l+sp1[1][1]]
				return csp_subpath_line_to([], [p,sp1[1]])
			else: 
				n = csp_normalized_normal(sp1,sp2,1.)
				p = [n[0]*l+sp2[1][0],n[1]*l+sp2[1][1]]
				return csp_subpath_line_to([], [sp2[1],p])
				
		def add_tangent(sp1,sp2,end = False,l=10.,r=10.) :
			# r is needed only for be compatible with add_arc
			if not end : 
				n = csp_normalized_slope(sp1,sp2,0.)
				p = [-n[0]*l+sp1[1][0],-n[1]*l+sp1[1][1]]
				return csp_subpath_line_to([], [p,sp1[1]])
			else: 
				n = csp_normalized_slope(sp1,sp2,1.)
				p = [n[0]*l+sp2[1][0],n[1]*l+sp2[1][1]]
				return csp_subpath_line_to([], [sp2[1],p])
	
		if not self.options.in_out_path and not self.options.plasma_prepare_corners and self.options.in_out_path_do_not_add_reference_point: 
			self.error("Warning! Extenstion is not said to do anything! Enable one of Create in-out paths or Prepare corners checkboxes or disable Do not add in-out referense point!")
			return

		# Add in-out-reference point if there is no one yet.		
		if ( (len(self.in_out_reference_points)==0 and self.options.in_out_path
			or not self.options.in_out_path and not self.options.plasma_prepare_corners )
			 and not self.options.in_out_path_do_not_add_reference_point) :
					self.options.orientation_points_count = "in-out reference point"		
					self.orientation()
			
		if self.options.in_out_path or self.options.plasma_prepare_corners:
			self.set_markers()
			add_func = {"Round":add_arc, "Perpendicular": add_normal, "Tangent": add_tangent}[self.options.in_out_path_type]
			if self.options.in_out_path_type == "Round" and self.options.in_out_path_len > self.options.in_out_path_radius*3/2*math.pi :
				self.error("In-out len is to big for in-out radius will cropp it to be r*3/2*pi!", "warning") 
			
			if self.selected_paths == {} and self.options.auto_select_paths:
				self.selected_paths = self.paths
				self.error(_("No paths are selected! Trying to work on all available paths."),"warning")

			if self.selected_paths == {}:
				self.error(_("Noting is selected. Please select something."),"warning")
			a = self.options.plasma_prepare_corners_tolerance
			corner_tolerance = cross([1.,0.], [math.cos(a),math.sin(a)])

			for layer in self.layers :
				if layer in self.selected_paths :
					max_dist =	self.transform_scalar(self.options.in_out_path_point_max_dist, layer, reverse=True)
					l = 		self.transform_scalar(self.options.in_out_path_len, layer, reverse=True)
					plasma_l = 	self.transform_scalar(self.options.plasma_prepare_corners_distance, layer, reverse=True)
					r = 		self.transform_scalar(self.options.in_out_path_radius, layer, reverse=True)
					l = min(l,r*3/2*math.pi)

					for path in self.selected_paths[layer]:
						csp = self.apply_transforms( path, cubicsuperpath.parsePath(path.get("d")) )
						csp = csp_remove_zerro_segments(csp)
						res = []

						for subpath in csp :
						# Find closes point to in-out reference point
						# If subpath is open skip this step 
							if self.options.in_out_path :
								# split and reverse path for further add in-out points
								if point_to_point_d2(subpath[0][1], subpath[-1][1]) < 1.e-10 :
									d = [1e100,1,1,1.]
									for p in self.in_out_reference_points : 
										d1 = csp_to_point_distance([subpath], p, dist_bounds = [0,max_dist], tolerance=.01)
										if d1[0] < d[0] : 
											d = d1[:]
											p_ = p
									if d[0] < max_dist**2 :
										# Lets find is there any angles near this point to put in-out path in 
										# the angle if it's possible 
										# remove last node to make iterations easier
										subpath[0][0] = subpath[-1][0]
										del subpath[-1]
										max_cross = [-1e100, None]
										for j in range(len(subpath)) :
											sp1,sp2,sp3 = subpath[j-2],subpath[j-1],subpath[j]
											if point_to_point_d2(sp2[1],p_)<max_dist**2:
												s1,s2 = csp_normalized_slope(sp1,sp2,1.), csp_normalized_slope(sp2,sp3,0.)
												max_cross = max(max_cross,[cross(s1,s2),j-1])
										# return back last point		
										subpath.append(subpath[0])
										if max_cross[1] !=None  and max_cross[0]>corner_tolerance :
											# there's an angle near the point
											j = max_cross[1]
											if j<0 : j -= 1
											if j!=0 :
												subpath	= csp_concat_subpaths(subpath[j:],subpath[:j+1])
										else :
											# have to cut path's segment
											d,i,j,t = d
											sp1,sp2,sp3 = csp_split(subpath[j-1],subpath[j],t)
											subpath = csp_concat_subpaths([sp2,sp3], subpath[j:], subpath[:j], [sp1,sp2]) 							

							if self.options.plasma_prepare_corners :
								# prepare corners
								# find corners and add some nodes
								# corner at path's start/end is ignored
								res_ = [subpath[0]]
								for sp2, sp3 in zip(subpath[1:],subpath[2:]) :
									sp1 = res_[-1]
									s1,s2 = csp_normalized_slope(sp1,sp2,1.), csp_normalized_slope(sp2,sp3,0.)
									if cross(s1,s2) > corner_tolerance :
										# got a corner to process
										S1,S2 = P(s1),P(s2)
										N = (S1-S2).unit()*plasma_l
										SP2= P(sp2[1])
										P1 = (SP2 + N)
										res_ += [
													[sp2[0],sp2[1],  (SP2+S1*plasma_l).to_list() ],
													[ (P1-N.ccw()/2 ).to_list(), P1.to_list(), (P1+N.ccw()/2).to_list()], 
													[(SP2-S2*plasma_l).to_list(), sp2[1],sp2[2]]
												]
									else: 
										res_ += [sp2]
								res_ += [sp3]
								subpath = res_
							if self.options.in_out_path :
								# finally add let's add in-out paths... 
								subpath = csp_concat_subpaths(
													add_func(subpath[0],subpath[1],False,l,r),
													subpath,
													add_func(subpath[-2],subpath[-1],True,l,r)
													)

							
							res += [ subpath ] 
							
							
						if self.options.in_out_path_replace_original_path :
							path.set("d", cubicsuperpath.formatPath( self.apply_transforms(path,res,True) ))
						else:	
							draw_csp(res, width=1, style=styles["in_out_path_style"] )
		
################################################################################
###		Arrangement: arranges paths by givven params
###		TODO move it to the bottom
################################################################################
	def arrangement(self) :
		paths = self.selected_paths
		surface = Polygon()
		polygons = []
		time_ = time.time()
		print_("Arrangement start at %s"%(time_))
		original_paths = []
		for layer in self.layers :
			if layer in paths :
				for path in paths[layer] :
					csp = cubicsuperpath.parsePath(path.get("d"))
					polygon = Polygon()
					for subpath in csp :
						for sp1, sp2 in zip(subpath,subpath[1:]) :
							polygon.add([csp_segment_convex_hull(sp1,sp2)])
					#print_("Redused edges count from", sum([len(poly) for poly in polygon.polygon ]) )
					polygon.hull()
					original_paths += [path]
					polygons += [polygon]
					
		print_("Paths hull computed in %s sec."%(time.time()-time_))
		print_("Got %s polygons having average %s edges each."% ( len(polygons), float(sum([ sum([len(poly) for poly in polygon.polygon]) for polygon in polygons ])) / len(polygons) ) )
		time_ = time.time()
		
#		material_width = self.options.arrangement_material_width
#		population = Arangement_Genetic(polygons, material_width)
#		population.add_random_species(1)
#		population.test_population_centroid()
##		return
		material_width = self.options.arrangement_material_width
		population = Arangement_Genetic(polygons, material_width)
		
		
		print_("Genetic algorithm start at %s"%(time_))
		start_time = time.time()
		time_ = time.time()
		
	

		population.add_random_species(50)
		#population.test(population.test_spiece_centroid)
		print_("Initial population done in %s"%(time.time()-time_))
		time_ = time.time()
		pop = copy.deepcopy(population)
		population_count = self.options.arrangement_population_count
		last_champ = -1
		champions_count = 0
		
		
		
		
		for i in range(population_count):
			population.leave_top_species(20)
			population.move_mutation_multiplier = random.random()/2
			
			population.order_mutation_factor = .2
			population.move_mutation_factor = 1.
			population.mutation_genes_count = [1,2]
			population.populate_species(250, 20)
			print_("Populate done at %s"%(time.time()-time_))			
			"""
			randomize = i%100 < 40
			if 	i%100 < 40 : 
				population.add_random_species(250)
			if  40<= i%100 < 100 : 
				population.mutation_genes_count = [1,max(2,int(population.genes_count/4))]  #[1,max(2,int(population.genes_count/2))] if 40<=i%100<60 else [1,max(2,int(population.genes_count/10))]
				population.move_mutation_multiplier = 1. if 40<=i%100<80 else .1
				population.move_mutation_factor = (-(i%100)/30+10/3) if 50<=i%100<100 else .5
				population.order_mutation_factor = 1./(i%100-79) if 80<=i%100<100 else 1.
				population.populate_species(250, 10)
			"""
			if self.options.arrangement_inline_test :
				population.test_inline()
			else:		
				population.test(population.test_spiece_centroid)
				
			print_("Test done at %s"%(time.time()-time_))
			draw_new_champ = False
			print_()

			
			if population.population[0][0]!= last_champ : 
				draw_new_champ = True
				improve = last_champ-population.population[0][0]
				last_champ = population.population[0][0]*1

			
			print_("Cicle %s done in %s"%(i,time.time()-time_))
			time_ = time.time()
			print_("%s incests been found"%population.inc)
			print_()

			if i == 0  or i == population_count-1 or draw_new_champ :
				colors = ["blue"]
				
				surface = population.test_spiece_centroid(population.population[0][1])
				b = surface.bounds()
				x,y = 400* (champions_count%10), 700*int(champions_count/10)
				surface.move(x-b[0],y-b[1])
				surface.draw(width=2, color=colors[0])
				draw_text("Step = %s\nSquare = %f\nSquare improvement = %f\nTime from start = %f"%(i,(b[2]-b[0])*(b[3]-b[1]),improve,time.time()-start_time),x,y-50)
				champions_count += 1
				"""
				spiece = population.population[0][1]
				poly = Polygon(copy.deepcopy(population.polygons[spiece[0][0]].polygon))
				poly.rotate(spiece[0][2]*math.pi2)
				surface  = Polygon(poly.polygon)
				poly.draw(width = 2, color= "Violet")
				for p in spiece[1:] :
					poly = Polygon(copy.deepcopy(population.polygons[p[0]].polygon))
					poly.rotate(p[2]*math.pi2)
					direction = [math.cos(p[1]*math.pi2), -math.sin(p[1]*math.pi2)]
					normalize(direction)
					c = surface.centroid()
					c1 = poly.centroid()
					poly.move(c[0]-c1[0]-direction[0]*400,c[1]-c1[1]-direction[1]*400)
					c = surface.centroid()
					c1 = poly.centroid()
					poly.draw(width = 5, color= "Violet")
					draw_pointer(c+c1,"Green","line")
					direction = normalize(direction)
					
					
					sin,cos = direction[0], direction[1]
					poly.rotate_(-sin,cos)
					surface.rotate_(-sin,cos)
#					poly.draw(color = "Violet",width=4)					
					surface.draw(color = "Orange",width=4)					
					poly.rotate_(sin,cos)
					surface.rotate_(sin,cos)


					poly.drop_into_direction(direction,surface)
					surface.add(poly)
				
				"""
		# Now we'll need apply transforms to original paths
		
		
	def __init__(self):
		inkex.Effect.__init__(self)
		self.OptionParser.add_option("-d", "--directory",					action="store", type="string", 		dest="directory", default="/home/",					help="Directory for gcode file")
		self.OptionParser.add_option("-f", "--filename",					action="store", type="string", 		dest="file", default="-1.0",						help="File name")			
		self.OptionParser.add_option("",   "--add-numeric-suffix-to-filename", action="store", type="inkbool",	dest="add_numeric_suffix_to_filename", default=True,help="Add numeric suffix to filename")			
		self.OptionParser.add_option("",   "--Zscale",						action="store", type="float", 		dest="Zscale", default="1.0",						help="Scale factor Z")				
		self.OptionParser.add_option("",   "--Zoffset",						action="store", type="float", 		dest="Zoffset", default="0.0",						help="Offset along Z")
		self.OptionParser.add_option("-s", "--Zsafe",						action="store", type="float", 		dest="Zsafe", default="0.5",						help="Z above all obstacles")
		self.OptionParser.add_option("-z", "--Zsurface",					action="store", type="float", 		dest="Zsurface", default="0.0",						help="Z of the surface")
		self.OptionParser.add_option("-c", "--Zdepth",						action="store", type="float", 		dest="Zdepth", default="-0.125",					help="Z depth of cut")
		self.OptionParser.add_option("",   "--Zstep",						action="store", type="float", 		dest="Zstep", default="-0.125",						help="Z step of cutting")		
		self.OptionParser.add_option("-p", "--feed",						action="store", type="float", 		dest="feed", default="4.0",							help="Feed rate in unit/min")

		self.OptionParser.add_option("",   "--biarc-tolerance",				action="store", type="float", 		dest="biarc_tolerance", default="1",				help="Tolerance used when calculating biarc interpolation.")				
		self.OptionParser.add_option("",   "--biarc-max-split-depth",		action="store", type="int", 		dest="biarc_max_split_depth", default="4",			help="Defines maximum depth of splitting while approximating using biarcs.")				
		self.OptionParser.add_option("",   "--path-to-gcode-order",			action="store", type="string", 		dest="path_to_gcode_order", default="path by path",	help="Defines cutting order path by path or layer by layer.")				
		self.OptionParser.add_option("",   "--path-to-gcode-depth-function",action="store", type="string", 		dest="path_to_gcode_depth_function", default="zd",	help="Path to gcode depth function.")				
		self.OptionParser.add_option("",   "--path-to-gcode-sort-paths",	action="store", type="inkbool",		dest="path_to_gcode_sort_paths", default=True,		help="Sort paths to reduse rapid distance.")		
		self.OptionParser.add_option("",   "--comment-gcode",				action="store", type="string", 		dest="comment_gcode", default="",					help="Comment Gcode")				
		self.OptionParser.add_option("",   "--comment-gcode-from-properties",action="store", type="inkbool", 	dest="comment_gcode_from_properties", default=False,help="Get additional comments from Object Properties")				
		self.OptionParser.add_option("",   "--comments",					action="store", type="string",	 	dest="comments", default="",						help="Select comments type")				



		self.OptionParser.add_option("",   "--tool-diameter",				action="store", type="float", 		dest="tool_diameter", default="3",					help="Tool diameter used for area cutting")		
		self.OptionParser.add_option("",   "--max-area-curves",				action="store", type="int", 		dest="max_area_curves", default="100",				help="Maximum area curves for each area")
		self.OptionParser.add_option("",   "--area-inkscape-radius",		action="store", type="float", 		dest="area_inkscape_radius", default="0",			help="Area curves overlaping (depends on tool diameter [0,0.9])")
		self.OptionParser.add_option("",   "--area-tool-overlap",			action="store", type="float", 		dest="area_tool_overlap", default="-10",			help="Radius for preparing curves using inkscape")
		self.OptionParser.add_option("",   "--unit",						action="store", type="string", 		dest="unit", default="G21 (All units in mm)",		help="Units")
		self.OptionParser.add_option("",   "--active-tab",					action="store", type="string", 		dest="active_tab", default="",						help="Defines which tab is active")

		self.OptionParser.add_option("",   "--area-fill-angle",				action="store", type="float", 		dest="area_fill_angle", default="0",					help="Fill area with lines heading this angle")
		self.OptionParser.add_option("",   "--area-fill-shift",				action="store", type="float", 		dest="area_fill_shift", default="0",					help="Shift the lines by tool d * shift")
		self.OptionParser.add_option("",   "--area-fill-method",			action="store", type="string", 		dest="area_fill_method", default="zig-zag",					help="Filling method either zig-zag or spiral")

		self.OptionParser.add_option("",   "--area-find-artefacts-diameter",action="store", type="float", 		dest="area_find_artefacts_diameter", default="1",					help="Artefacts seeking radius")
		self.OptionParser.add_option("",   "--area-find-artefacts-action",	action="store", type="string",	 	dest="area_find_artefacts_action", default="mark with an arrow",	help="Artefacts action type")

		self.OptionParser.add_option("",   "--auto_select_paths",			action="store", type="inkbool",		dest="auto_select_paths", default=True,				help="Select all paths if nothing is selected.")		

		self.OptionParser.add_option("",   "--loft-distances",				action="store", type="string", 		dest="loft_distances", default="10",				help="Distances between paths.")
		self.OptionParser.add_option("",   "--loft-direction",				action="store", type="string", 		dest="loft_direction", default="crosswise",			help="Direction of loft's interpolation.")
		self.OptionParser.add_option("",   "--loft-interpolation-degree",	action="store", type="float",		dest="loft_interpolation_degree", default="2",		help="Which interpolation use to loft the paths smooth interpolation or staright.")

		self.OptionParser.add_option("",   "--min-arc-radius",				action="store", type="float", 		dest="min_arc_radius", default=".1",				help="All arc having radius less than minimum will be considered as straight line")		

		self.OptionParser.add_option("",   "--engraving-sharp-angle-tollerance",action="store", type="float",	dest="engraving_sharp_angle_tollerance", default="150",		help="All angles thar are less than engraving-sharp-angle-tollerance will be thought sharp")		
		self.OptionParser.add_option("",   "--engraving-max-dist",			action="store", type="float", 		dest="engraving_max_dist", default="10",					help="Distanse from original path where engraving is not needed (usualy it's cutting tool diameter)")		
		self.OptionParser.add_option("",   "--engraving-newton-iterations", action="store", type="int", 		dest="engraving_newton_iterations", default="4",			help="Number of sample points used to calculate distance")		
		self.OptionParser.add_option("",   "--engraving-draw-calculation-paths",action="store", type="inkbool",	dest="engraving_draw_calculation_paths", default=False,		help="Draw additional graphics to debug engraving path")		
		self.OptionParser.add_option("",   "--engraving-cutter-shape-function",action="store", type="string", 	dest="engraving_cutter_shape_function", default="w",		help="Cutter shape function z(w). Ex. cone: w. ")

		self.OptionParser.add_option("",   "--lathe-width",					action="store", type="float", 		dest="lathe_width", default=10.,							help="Lathe width")
		self.OptionParser.add_option("",   "--lathe-fine-cut-width",		action="store", type="float", 		dest="lathe_fine_cut_width", default=1.,					help="Fine cut width")
		self.OptionParser.add_option("",   "--lathe-fine-cut-count",		action="store", type="int", 		dest="lathe_fine_cut_count", default=1.,					help="Fine cut count")
		self.OptionParser.add_option("",   "--lathe-create-fine-cut-using",	action="store", type="string",		dest="lathe_create_fine_cut_using", default="Move path",			help="Create fine cut using")
		self.OptionParser.add_option("",   "--lathe-x-axis-remap",			action="store", type="string", 		dest="lathe_x_axis_remap", default="X",						help="Lathe X axis remap")
		self.OptionParser.add_option("",   "--lathe-z-axis-remap",			action="store", type="string", 		dest="lathe_z_axis_remap", default="Z",						help="Lathe Z axis remap")

		self.OptionParser.add_option("",   "--lathe-rectangular-cutter-width",action="store", type="float", 	dest="lathe_rectangular_cutter_width", default="4",		help="Rectangular cutter width")

		self.OptionParser.add_option("",   "--create-log",					action="store", type="inkbool", 	dest="log_create_log", default=False,				help="Create log files")
		self.OptionParser.add_option("",   "--log-filename",				action="store", type="string", 		dest="log_filename", default='',					help="Create log files")

		self.OptionParser.add_option("",   "--orientation-points-count",	action="store", type="string", 		dest="orientation_points_count", default="2",			help="Orientation points count")
		self.OptionParser.add_option("",   "--tools-library-type",			action="store", type="string", 		dest="tools_library_type", default='cylinder cutter',	help="Create tools definition")

		self.OptionParser.add_option("",   "--dxfpoints-action",			action="store", type="string", 		dest="dxfpoints_action", default='replace',			help="dxfpoint sign toggle")
																										  
		self.OptionParser.add_option("",   "--help-language",				action="store", type="string", 		dest="help_language", default='http://www.cnc-club.ru/forum/viewtopic.php?f=33&t=35',	help="Open help page in webbrowser.")

		self.OptionParser.add_option("",   "--offset-radius",				action="store", type="float", 		dest="offset_radius", default=10.,		help="Offset radius")
		self.OptionParser.add_option("",   "--offset-step",					action="store", type="float", 		dest="offset_step", default=10.,		help="Offset step")
		self.OptionParser.add_option("",   "--offset-draw-clippend-path",	action="store", type="inkbool",		dest="offset_draw_clippend_path", default=False,		help="Draw clipped path")		
		self.OptionParser.add_option("",   "--offset-just-get-distance",	action="store", type="inkbool",		dest="offset_just_get_distance", default=False,		help="Don't do offset just get distance")		
	
		self.OptionParser.add_option("",   "--arrangement-material-width",	action="store", type="float",		dest="arrangement_material_width", default=500,		help="Materials width for arrangement")		
		self.OptionParser.add_option("",   "--arrangement-population-count",action="store", type="int",			dest="arrangement_population_count", default=100,	help="Genetic algorithm populations count")		
		self.OptionParser.add_option("",   "--arrangement-inline-test",		action="store", type="inkbool", 	dest="arrangement_inline_test", default=False,	help="Use C-inline test (some additional packets will be needed)")


		self.OptionParser.add_option("",   "--postprocessor",				action="store", type="string", 		dest="postprocessor", default='',			help="Postprocessor command.")
		self.OptionParser.add_option("",   "--postprocessor-custom",		action="store", type="string", 		dest="postprocessor_custom", default='',	help="Postprocessor custom command.")
	
		self.OptionParser.add_option("",   "--graffiti-max-seg-length",		action="store", type="float", 		dest="graffiti_max_seg_length", default=1.,	help="Graffiti maximum segment length.")
		self.OptionParser.add_option("",   "--graffiti-min-radius",			action="store", type="float", 		dest="graffiti_min_radius", default=10.,	help="Graffiti minimal connector's radius.")
		self.OptionParser.add_option("",   "--graffiti-start-pos",			action="store", type="string", 		dest="graffiti_start_pos", default="(0;0)",	help="Graffiti Start position (x;y).")
		self.OptionParser.add_option("",   "--graffiti-create-linearization-preview",	action="store", type="inkbool", 	dest="graffiti_create_linearization_preview", default=True,	help="Graffiti create linearization preview.")
		self.OptionParser.add_option("",   "--graffiti-create-preview",		action="store", type="inkbool", 	dest="graffiti_create_preview", default=True,	help="Graffiti create preview.")
		self.OptionParser.add_option("",   "--graffiti-preview-size",		action="store", type="int", 		dest="graffiti_preview_size", default=800,	help="Graffiti preview's size.")
		self.OptionParser.add_option("",   "--graffiti-preview-emmit",		action="store", type="int", 		dest="graffiti_preview_emmit", default=800,	help="Preview's paint emmit (pts/s).")


		self.OptionParser.add_option("",   "--in-out-path",					action="store", type="inkbool", 	dest="in_out_path",	default=True,			help="Create in-out paths")
		self.OptionParser.add_option("",   "--in-out-path-do-not-add-reference-point",	action="store", type="inkbool", dest="in_out_path_do_not_add_reference_point", default=False,	help="Just add reference in-out point")
		self.OptionParser.add_option("",   "--in-out-path-point-max-dist",	action="store", type="float", 		dest="in_out_path_point_max_dist", default=10.,	help="In-out path max distance to reference point")
		self.OptionParser.add_option("",   "--in-out-path-type",			action="store", type="string", 		dest="in_out_path_type", default="Round",	help="In-out path type")
		self.OptionParser.add_option("",   "--in-out-path-len",				action="store", type="float", 		dest="in_out_path_len", default=10.,		help="In-out path length")
		self.OptionParser.add_option("",   "--in-out-path-replace-original-path",action="store", type="inkbool", dest="in_out_path_replace_original_path", default=False,	help="Replace original path")
		self.OptionParser.add_option("",   "--in-out-path-radius",			action="store", type="float", 		dest="in_out_path_radius", default=10.,		help="In-out path radius for round path")

		self.OptionParser.add_option("",   "--plasma-prepare-corners",		action="store", type="inkbool",		dest="plasma_prepare_corners", default=True,	help="Prepare corners")
		self.OptionParser.add_option("",   "--plasma-prepare-corners-distance", action="store", type="float",	dest="plasma_prepare_corners_distance", default=10.,help="Stepout distance for corners")
		self.OptionParser.add_option("",   "--plasma-prepare-corners-tolerance", action="store", type="float",	dest="plasma_prepare_corners_tolerance", default=10.,help="Maximum angle for corner (0-180 deg)")

		self.default_tool = {
					"name": "Default tool",
					"id": "default tool",
					"diameter":10.,
					"shape": "10",
					"penetration angle":90.,
					"penetration feed":100.,
					"depth step":1.,
					"feed":400.,
					"in trajectotry":"",
					"out trajectotry":"",
					"gcode before path":"",
					"gcode after path":"",
					"sog":"",
					"spindle rpm":"",
					"CW or CCW":"",
					"tool change gcode":" ",
					"comments":"",
					"4th axis meaning": " ",
					"4th axis scale": 1.,
					"4th axis offset": 0.,
					"passing feed":"800",					
					"fine feed":"800",					
				}			
		self.tools_field_order = [
					'name',
					'id',
					'diameter',
					'feed',
					'shape',
					'penetration angle',
					'penetration feed',
					"passing feed",
					'depth step',
					"in trajectotry",
					"out trajectotry",
					"gcode before path",
					"gcode after path",
					"sog",
					"spinlde rpm",
					"CW or CCW",
					"tool change gcode",
					"comments",
				]


	def parse_curve(self, p, layer, w = None, f = None):
			c = []
			if len(p)==0 : 
				return []
			p = self.transform_csp(p, layer)
			

			### Sort to reduce Rapid distance	
			k = range(1,len(p))
			keys = [0]
			while len(k)>0:
				end = p[keys[-1]][-1][1]
				dist = None
				for i in range(len(k)):
					start = p[k[i]][0][1]
					dist = max(   ( -( ( end[0]-start[0])**2+(end[1]-start[1])**2 ) ,i)	,   dist )
				keys += [k[dist[1]]]
				del k[dist[1]]
			for k in keys:
				subpath = p[k]
				c += [ [	[subpath[0][1][0],subpath[0][1][1]]   , 'move', 0, 0] ]
				for i in range(1,len(subpath)):
					sp1 = [  [subpath[i-1][j][0], subpath[i-1][j][1]] for j in range(3)]
					sp2 = [  [subpath[i  ][j][0], subpath[i  ][j][1]] for j in range(3)]
					c += biarc(sp1,sp2,0,0) if w==None else biarc(sp1,sp2,-f(w[k][i-1]),-f(w[k][i]))
#					l1 = biarc(sp1,sp2,0,0) if w==None else biarc(sp1,sp2,-f(w[k][i-1]),-f(w[k][i]))
#					print_((-f(w[k][i-1]),-f(w[k][i]), [i1[5] for i1 in l1]) )
				c += [ [ [subpath[-1][1][0],subpath[-1][1][1]]  ,'end',0,0] ]
			return c


################################################################################
### 	Draw csp 
################################################################################

	def draw_csp(self, csp, layer=None, group=None, fill='none', stroke='#178ade', width=0.354, style=None):
		if layer!=None :
			csp = self.transform_csp(csp,layer,reverse=True)
		if group==None and layer==None:
			group = self.document.getroot()
		elif group==None and layer!=None :
			group = layer
		csp = self.apply_transforms(group,csp, reverse=True)
		if style!=None :
			return draw_csp(csp, group=group, style=style)
		else :
			return draw_csp(csp, group=group, fill=fill, stroke=stroke, width=width)
				



	def draw_curve(self, curve, layer, group=None, style=styles["biarc_style"]):
		self.set_markers()

		for i in [0,1]:
			style['biarc%s_r'%i] = simplestyle.parseStyle(style['biarc%s'%i])
			style['biarc%s_r'%i]["marker-start"] = "url(#DrawCurveMarker_r)"
			del(style['biarc%s_r'%i]["marker-end"])
			style['biarc%s_r'%i] = simplestyle.formatStyle(style['biarc%s_r'%i])
		
		if group==None:
			if "preview_groups" not in dir(self) :
				self.preview_groups = { layer: inkex.etree.SubElement( self.layers[min(1,len(self.layers)-1)], inkex.addNS('g','svg'), {"gcodetools": "Preview group"} ) }
			elif layer not in self.preview_groups :
				self.preview_groups[layer] = inkex.etree.SubElement( self.layers[min(1,len(self.layers)-1)], inkex.addNS('g','svg'), {"gcodetools": "Preview group"} )
			group = self.preview_groups[layer]

		s, arcn = '', 0
		
		transform = self.get_transforms(group)
		if transform != [] : 
			transform = self.reverse_transform(transform)
			transform = simpletransform.formatTransform(transform)
		
		a,b,c = [0.,0.], [1.,0.], [0.,1.]
		k = (b[0]-a[0])*(c[1]-a[1])-(c[0]-a[0])*(b[1]-a[1])
		a,b,c = self.transform(a, layer, True), self.transform(b, layer, True), self.transform(c, layer, True)
		if ((b[0]-a[0])*(c[1]-a[1])-(c[0]-a[0])*(b[1]-a[1]))*k > 0 : reverse_angle = 1
		else : reverse_angle = -1 
		for sk in curve:
			si = sk[:]
			si[0], si[2] = self.transform(si[0], layer, True), (self.transform(si[2], layer, True) if type(si[2])==type([]) and len(si[2])==2 else si[2])
			
			if s!='':
				if s[1] == 'line':
					attr = {	'style': style['line'],
								'd':'M %s,%s L %s,%s' % (s[0][0], s[0][1], si[0][0], si[0][1]),
								"gcodetools": "Preview",
							}
					if transform != [] :
						attr["transform"] = transform		
					inkex.etree.SubElement(	group, inkex.addNS('path','svg'),  attr	)
				elif s[1] == 'arc':
					arcn += 1
					sp = s[0]
					c = s[2]
					s[3] = s[3]*reverse_angle
						
					a =  ( (P(si[0])-P(c)).angle() - (P(s[0])-P(c)).angle() )%math.pi2 #s[3]
					if s[3]*a<0: 
							if a>0:	a = a-math.pi2
							else: a = math.pi2+a
					r = math.sqrt( (sp[0]-c[0])**2 + (sp[1]-c[1])**2 )
					a_st = ( math.atan2(sp[0]-c[0],- (sp[1]-c[1])) - math.pi/2 ) % (math.pi*2)
					st = style['biarc%s' % (arcn%2)][:]
					if a>0:
						a_end = a_st+a
						st = style['biarc%s'%(arcn%2)]
					else: 
						a_end = a_st*1
						a_st = a_st+a
						st = style['biarc%s_r'%(arcn%2)]
					
					attr = {
							'style': st,
							 inkex.addNS('cx','sodipodi'):		str(c[0]),
							 inkex.addNS('cy','sodipodi'):		str(c[1]),
							 inkex.addNS('rx','sodipodi'):		str(r),
							 inkex.addNS('ry','sodipodi'):		str(r),
							 inkex.addNS('start','sodipodi'):	str(a_st),
							 inkex.addNS('end','sodipodi'):		str(a_end),
							 inkex.addNS('open','sodipodi'):	'true',
							 inkex.addNS('type','sodipodi'):	'arc',
							 "gcodetools": "Preview",
							}	
						
					if transform != [] :
						attr["transform"] = transform	
					inkex.etree.SubElement(	group, inkex.addNS('path','svg'), attr)
			s = si
	

	def check_dir(self):
		if self.options.directory[-1] not in ["/","\\"]:
			if "\\" in self.options.directory :
				self.options.directory += "\\"
			else :
				self.options.directory += "/"
		print_("Checking directory: '%s'"%self.options.directory)
		if (os.path.isdir(self.options.directory)):
			if (os.path.isfile(self.options.directory+'header')):
				f = open(self.options.directory+'header', 'r')
				self.header = f.read()
				f.close()
			else:
				self.header = defaults['header']
			if (os.path.isfile(self.options.directory+'footer')):
				f = open(self.options.directory+'footer','r')
				self.footer = f.read()
				f.close()
			else:
				self.footer = defaults['footer']
			self.header += self.options.unit + "\n" 
			
		else: 
			self.error(_("Directory does not exist! Please specify existing directory at Preferences tab!"),"error")
			return False

		if self.options.add_numeric_suffix_to_filename :
			dir_list = os.listdir(self.options.directory)
			if "." in self.options.file : 
				r = re.match(r"^(.*)(\..*)$",self.options.file)
				ext = r.group(2)
				name = r.group(1)
			else: 	
				ext = ""
				name = self.options.file
			max_n = 0
			for s in dir_list :
				r = re.match(r"^%s_0*(\d+)%s$"%(re.escape(name),re.escape(ext) ), s)
				if r :
					max_n = max(max_n,int(r.group(1)))
			filename = name + "_" + ( "0"*(4-len(str(max_n+1))) + str(max_n+1) ) + ext
			self.options.file = filename

		if self.options.directory[-1] not in ["/","\\"]:
			if "\\" in self.options.directory :
				self.options.directory += "\\"
			else :
				self.options.directory += "/"

		try: 	
			f = open(self.options.directory+self.options.file, "w")	
			f.close()							
		except:
			self.error(_("Can not write to specified file!\n%s"%(self.options.directory+self.options.file)),"error")
			return False
		return True
			


################################################################################
###
###		Generate Gcode
###		Generates Gcode on given curve.
###
###		Curve definition [start point, type = {'arc','line','move','end'}, arc center, arc angle, end point, [zstart, zend]]		
###
################################################################################
	def generate_gcode(self, curve, layer, depth):
		Zauto_scale = self.Zauto_scale[layer]
		tool = self.tools[layer][0]
		g = ""

		def c(c):
			c = [c[i] if i<len(c) else None for i in range(6)]
			if c[5] == 0 : c[5]=None
			s,s1 = [" X", " Y", " Z", " I", " J", " K"], ["","","","","",""]
			m,a = [1,1,self.options.Zscale*Zauto_scale,1,1,self.options.Zscale*Zauto_scale], [0,0,self.options.Zoffset,0,0,0]
			r = ''	
			for i in range(6):
				if c[i]!=None:
					r += s[i] + ("%f" % (c[i]*m[i]+a[i])) + s1[i]
			return r

		def calculate_angle(a, current_a):
			return  min(					
						[abs(a-current_a%math.pi2+math.pi2), a+current_a-current_a%math.pi2+math.pi2],
						[abs(a-current_a%math.pi2-math.pi2), a+current_a-current_a%math.pi2-math.pi2],
						[abs(a-current_a%math.pi2),			 a+current_a-current_a%math.pi2])[1]
		if len(curve)==0 : return ""	
				
		try :
			self.last_used_tool == None
		except :
			self.last_used_tool = None
		print_("working on curve")
		print_(curve)
		
		if tool != self.last_used_tool :
			g += ( "(Change tool to %s)\n" % re.sub("\"'\(\)\\\\"," ",tool["name"]) ) + tool["tool change gcode"] + "\n"

		lg, zs, f =  'G00', self.options.Zsafe, " F%f"%tool['feed'] 
		current_a = 0
		go_to_safe_distance = "G00" + c([None,None,zs]) + "\n" 
		penetration_feed = " F%s"%tool['penetration feed'] 
		for i in range(1,len(curve)):
		#	Creating Gcode for curve between s=curve[i-1] and si=curve[i] start at s[0] end at s[4]=si[0]
			s, si = curve[i-1], curve[i]
			feed = f if lg not in ['G01','G02','G03'] else ''
			if s[1]	== 'move':
				g += go_to_safe_distance + "G00" + c(si[0]) + "\n" + tool['gcode before path'] + "\n"
				lg = 'G00'
			elif s[1] == 'end':
				g += go_to_safe_distance + tool['gcode after path'] + "\n"
				lg = 'G00'
			elif s[1] == 'line':
				if tool['4th axis meaning'] == "tangent knife" : 
					a = atan2(si[0][0]-s[0][0],si[0][1]-s[0][1])
					a = calculate_angle(a, current_a)
					g+="G01 A%s\n" % (a*tool['4th axis scale']+tool['4th axis offset'])
					current_a = a
				if lg=="G00": g += "G01" + c([None,None,s[5][0]+depth]) + penetration_feed +" (Penetrate)\n"	
				g += "G01" +c(si[0]+[s[5][1]+depth]) + feed + "\n"
				lg = 'G01'
			elif s[1] == 'arc':
				r = [(s[2][0]-s[0][0]), (s[2][1]-s[0][1])]
				if tool['4th axis meaning'] == "tangent knife" : 
					if s[3]<0 : # CW
						a1 = atan2(s[2][1]-s[0][1],-s[2][0]+s[0][0]) + math.pi 
					else: #CCW
						a1 = atan2(-s[2][1]+s[0][1],s[2][0]-s[0][0]) + math.pi
					a = calculate_angle(a1, current_a)
					g+="G01 A%s\n" % (a*tool['4th axis scale']+tool['4th axis offset'])
					current_a = a
					axis4 = " A%s"%((current_a+s[3])*tool['4th axis scale']+tool['4th axis offset'])
					current_a = current_a+s[3]
				else : axis4 = ""
				if lg=="G00": g += "G01" + c([None,None,s[5][0]+depth]) + penetration_feed + " (Penetrate)\n"				
				if (r[0]**2 + r[1]**2)>self.options.min_arc_radius**2:
					r1, r2 = (P(s[0])-P(s[2])), (P(si[0])-P(s[2]))
					if abs(r1.mag()-r2.mag()) < 0.001 :
						g += ("G02" if s[3]<0 else "G03") + c(si[0]+[ s[5][1]+depth, (s[2][0]-s[0][0]),(s[2][1]-s[0][1])  ]) + feed + axis4 + "\n"
					else:
						r = (r1.mag()+r2.mag())/2
						g += ("G02" if s[3]<0 else "G03") + c(si[0]+[s[5][1]+depth]) + " R%f" % (r) + feed  + axis4 + "\n"
					lg = 'G02'
				else:
					if tool['4th axis meaning'] == "tangent knife" : 
						a = atan2(si[0][0]-s[0][0],si[0][1]-s[0][1]) + math.pi
						a = calculate_angle(a, current_a)
						g+="G01 A%s\n" % (a*tool['4th axis scale']+tool['4th axis offset'])
						current_a = a
					g += "G01" +c(si[0]+[s[5][1]+depth]) + feed + "\n"
					lg = 'G01'
		if si[1] == 'end':
			g += go_to_safe_distance + tool['gcode after path'] + "\n"
		return g


	def get_transforms(self,g):
		root = self.document.getroot()
		trans = []
		while (g!=root):
			if 'transform' in g.keys():
				t = g.get('transform')
				t = simpletransform.parseTransform(t)
				trans = simpletransform.composeTransform(t,trans) if trans != [] else t
				print_(trans)
			g=g.getparent()
		return trans 
	
	def reverse_transform(self,transform):
		trans = numpy.array(transform + [[0,0,1]])
		if numpy.linalg.det(trans)!=0 :
			trans = numpy.linalg.inv(trans).tolist()[:2]		
			return trans
		else :
		 return transform
		

	def apply_transforms(self,g,csp, reverse=False):
		trans = self.get_transforms(g)
		if trans != []:
			if not reverse :
				simpletransform.applyTransformToPath(trans, csp)
			else :
				simpletransform.applyTransformToPath(self.reverse_transform(trans), csp)
		return csp
		
		

	def transform_scalar(self,x,layer,reverse=False):
		return self.transform([x,0],layer,reverse)[0] - self.transform([0,0],layer,reverse)[0]

	def transform(self,source_point, layer, reverse=False):
		if layer not in self.transform_matrix:
			for i in range(self.layers.index(layer),-1,-1):
				if self.layers[i] in self.orientation_points : 
					break
			if self.layers[i] not in self.orientation_points :
				self.error(_("Orientation points for '%s' layer have not been found! Please add orientation points using Orientation tab!") % layer.get(inkex.addNS('label','inkscape')),"no_orientation_points")
			elif self.layers[i] in self.transform_matrix :
				self.transform_matrix[layer] = self.transform_matrix[self.layers[i]]
				self.Zcoordinates[layer] = self.Zcoordinates[self.layers[i]]
			else :
				orientation_layer = self.layers[i]
				if len(self.orientation_points[orientation_layer])>1 : 
					self.error(_("There are more than one orientation point groups in '%s' layer") % orientation_layer.get(inkex.addNS('label','inkscape')),"more_than_one_orientation_point_groups")
				points = self.orientation_points[orientation_layer][0]
				if len(points)==2:
					points += [ [ [(points[1][0][1]-points[0][0][1])+points[0][0][0], -(points[1][0][0]-points[0][0][0])+points[0][0][1]], [-(points[1][1][1]-points[0][1][1])+points[0][1][0], points[1][1][0]-points[0][1][0]+points[0][1][1]] ] ]
				if len(points)==3:
					print_("Layer '%s' Orientation points: " % orientation_layer.get(inkex.addNS('label','inkscape')))
					for point in points:
						print_(point)
					#	Zcoordinates definition taken from Orientatnion point 1 and 2 
					self.Zcoordinates[layer] = [max(points[0][1][2],points[1][1][2]), min(points[0][1][2],points[1][1][2])]
					matrix = numpy.array([
								[points[0][0][0], points[0][0][1], 1, 0, 0, 0, 0, 0, 0],
								[0, 0, 0, points[0][0][0], points[0][0][1], 1, 0, 0, 0],
								[0, 0, 0, 0, 0, 0, points[0][0][0], points[0][0][1], 1],
								[points[1][0][0], points[1][0][1], 1, 0, 0, 0, 0, 0, 0],
								[0, 0, 0, points[1][0][0], points[1][0][1], 1, 0, 0, 0],
								[0, 0, 0, 0, 0, 0, points[1][0][0], points[1][0][1], 1],
								[points[2][0][0], points[2][0][1], 1, 0, 0, 0, 0, 0, 0],
								[0, 0, 0, points[2][0][0], points[2][0][1], 1, 0, 0, 0],
								[0, 0, 0, 0, 0, 0, points[2][0][0], points[2][0][1], 1]
							])
								
					if numpy.linalg.det(matrix)!=0 :
						m = numpy.linalg.solve(matrix,
							numpy.array(
								[[points[0][1][0]], [points[0][1][1]], [1], [points[1][1][0]], [points[1][1][1]], [1], [points[2][1][0]], [points[2][1][1]], [1]]	
										)
							).tolist()
						self.transform_matrix[layer] = [[m[j*3+i][0] for i in range(3)] for j in range(3)]
					
					else :
						self.error(_("Orientation points are wrong! (if there are two orientation points they should not be the same. If there are three orientation points they should not be in a straight line.)"),"wrong_orientation_points")
				else :
					self.error(_("Orientation points are wrong! (if there are two orientation points they should not be the same. If there are three orientation points they should not be in a straight line.)"),"wrong_orientation_points")

			self.transform_matrix_reverse[layer] = numpy.linalg.inv(self.transform_matrix[layer]).tolist()		
			print_("\n Layer '%s' transformation matrixes:" % layer.get(inkex.addNS('label','inkscape')) )
			print_(self.transform_matrix)
			print_(self.transform_matrix_reverse)

			###self.Zauto_scale[layer]  = math.sqrt( (self.transform_matrix[layer][0][0]**2 + self.transform_matrix[layer][1][1]**2)/2 )
			### Zautoscale is absolete
			self.Zauto_scale[layer] = 1
			print_("Z automatic scale = %s (computed according orientation points)" % self.Zauto_scale[layer])

		x,y = source_point[0], source_point[1]
		if not reverse :
			t = self.transform_matrix[layer]
		else :
			t = self.transform_matrix_reverse[layer]
		return [t[0][0]*x+t[0][1]*y+t[0][2], t[1][0]*x+t[1][1]*y+t[1][2]]


	def transform_csp(self, csp_, layer, reverse = False):
		csp = [  [ [csp_[i][j][0][:],csp_[i][j][1][:],csp_[i][j][2][:]]  for j in range(len(csp_[i])) ]   for i in range(len(csp_)) ]
		for i in xrange(len(csp)):
			for j in xrange(len(csp[i])): 
				for k in xrange(len(csp[i][j])): 
					csp[i][j][k] = self.transform(csp[i][j][k],layer, reverse)
		return csp
	
		
################################################################################
###		Errors handling function, notes are just printed into Logfile, 
###		warnings are printed into log file and warning message is displayed but
###		extension continues working, errors causes log and execution is halted
###		Notes, warnings adn errors could be assigned to space or comma or dot 
###		sepparated strings (case is ignoreg).
################################################################################
	def error(self, s, type_= "Warning"):
		notes = "Note "
		warnings = """
						Warning tools_warning
						orientation_warning
						bad_orientation_points_in_some_layers
						more_than_one_orientation_point_groups
						more_than_one_tool
						orientation_have_not_been_defined
						tool_have_not_been_defined
						selection_does_not_contain_paths
						selection_does_not_contain_paths_will_take_all
						selection_is_empty_will_comupe_drawing
						selection_contains_objects_that_are_not_paths
						Continue
						"""
		errors = """
						Error 	
						wrong_orientation_points	
						area_tools_diameter_error
						no_tool_error
						active_layer_already_has_tool
						active_layer_already_has_orientation_points
					"""
		s = str(s)
		if type_.lower() in re.split("[\s\n,\.]+", errors.lower()) :
			print_(s)
			inkex.errormsg(s+"\n")		
			sys.exit()
		elif type_.lower() in re.split("[\s\n,\.]+", warnings.lower()) :
			print_(s)
			inkex.errormsg(s+"\n")		
		elif type_.lower() in re.split("[\s\n,\.]+", notes.lower()) :
			print_(s)
		else :
			print_(s)
			inkex.errormsg(s)		
			sys.exit()
	

################################################################################
###		Set markers
################################################################################
	def set_markers(self) :
		self.get_defs()
		# Add marker to defs if it doesnot exists
		if "CheckToolsAndOPMarker" not in self.defs : 
			defs = inkex.etree.SubElement( self.document.getroot(), inkex.addNS("defs","svg"))
			marker = inkex.etree.SubElement( defs, inkex.addNS("marker","svg"), {"id":"CheckToolsAndOPMarker","orient":"auto","refX":"-4","refY":"-1.687441","style":"overflow:visible"})
			inkex.etree.SubElement( marker, inkex.addNS("path","svg"), 
	
					{	"d":"	m -4.588864,-1.687441 0.0,0.0 L -9.177728,0.0 c 0.73311,-0.996261 0.728882,-2.359329 0.0,-3.374882",
						"style": "fill:#000044; fill-rule:evenodd;stroke:none;"	}
				)

		if "DrawCurveMarker" not in self.defs : 
			defs = inkex.etree.SubElement( self.document.getroot(), inkex.addNS("defs","svg"))
			marker = inkex.etree.SubElement( defs, inkex.addNS("marker","svg"), {"id":"DrawCurveMarker","orient":"auto","refX":"-4","refY":"-1.687441","style":"overflow:visible"})
			inkex.etree.SubElement( marker, inkex.addNS("path","svg"), 
					{	"d":"m -4.588864,-1.687441 0.0,0.0 L -9.177728,0.0 c 0.73311,-0.996261 0.728882,-2.359329 0.0,-3.374882",
						"style": "fill:#000044; fill-rule:evenodd;stroke:none;"	}
				)

		if "DrawCurveMarker_r" not in self.defs : 
			defs = inkex.etree.SubElement( self.document.getroot(), inkex.addNS("defs","svg"))
			marker = inkex.etree.SubElement( defs, inkex.addNS("marker","svg"), {"id":"DrawCurveMarker_r","orient":"auto","refX":"4","refY":"-1.687441","style":"overflow:visible"})
			inkex.etree.SubElement( marker, inkex.addNS("path","svg"), 
					{	"d":"m 4.588864,-1.687441 0.0,0.0 L 9.177728,0.0 c -0.73311,-0.996261 -0.728882,-2.359329 0.0,-3.374882",
						"style": "fill:#000044; fill-rule:evenodd;stroke:none;"	}
				)

		if "InOutPathMarker" not in self.defs : 
			defs = inkex.etree.SubElement( self.document.getroot(), inkex.addNS("defs","svg"))
			marker = inkex.etree.SubElement( defs, inkex.addNS("marker","svg"), {"id":"InOutPathMarker","orient":"auto","refX":"-4","refY":"-1.687441","style":"overflow:visible"})
			inkex.etree.SubElement( marker, inkex.addNS("path","svg"), 
					{	"d":"m -4.588864,-1.687441 0.0,0.0 L -9.177728,0.0 c 0.73311,-0.996261 0.728882,-2.359329 0.0,-3.374882",
						"style": "fill:#0072a7; fill-rule:evenodd;stroke:none;"	}
				)


	
################################################################################
###		Get defs from svg
################################################################################
	def get_defs(self) :
		self.defs = {}
		def recursive(g) :
			for i in g:
				if i.tag == inkex.addNS("defs","svg") : 
					for j in i: 
						self.defs[j.get("id")] = i
				if i.tag ==inkex.addNS("g",'svg') :
					recursive(i)
		recursive(self.document.getroot())


################################################################################
###
###		Get Gcodetools info from the svg
###
################################################################################
	def get_info(self):
		self.selected_paths = {}
		self.paths = {}		
		self.tools = {}
		self.orientation_points = {}
		self.graffiti_reference_points = {}
		self.layers = [self.document.getroot()]
		self.Zcoordinates = {}
		self.transform_matrix = {}
		self.transform_matrix_reverse = {}
		self.Zauto_scale = {}
		self.in_out_reference_points = []
		self.my3Dlayer = None

		def recursive_search(g, layer, selected=False):
			items = g.getchildren()
			items.reverse()
			for i in items:
				if selected:
					self.selected[i.get("id")] = i
				if i.tag == inkex.addNS("g",'svg') and i.get(inkex.addNS('groupmode','inkscape')) == 'layer':
					if i.get(inkex.addNS('label','inkscape')) == '3D' :
						self.my3Dlayer=i
					else :
						self.layers += [i]
						recursive_search(i,i)

				elif i.get('gcodetools') == "Gcodetools orientation group" :
					points = self.get_orientation_points(i)
					if points != None :
						self.orientation_points[layer] = self.orientation_points[layer]+[points[:]] if layer in self.orientation_points else [points[:]]
						print_("Found orientation points in '%s' layer: %s" % (layer.get(inkex.addNS('label','inkscape')), points))
					else :
						self.error(_("Warning! Found bad orientation points in '%s' layer. Resulting Gcode could be corrupt!") % layer.get(inkex.addNS('label','inkscape')), "bad_orientation_points_in_some_layers") 

				#Need to recognise old files ver 1.6.04 and earlier
				elif i.get("gcodetools") == "Gcodetools tool definition" or i.get("gcodetools") == "Gcodetools tool defenition"  :
					tool = self.get_tool(i)
					self.tools[layer] = self.tools[layer] + [tool.copy()] if layer in self.tools else [tool.copy()]
					print_("Found tool in '%s' layer: %s" % (layer.get(inkex.addNS('label','inkscape')), tool))

				elif i.get("gcodetools") == "Gcodetools graffiti reference point" :
					point = self.get_graffiti_reference_points(i)
					if point != [] :
						self.graffiti_reference_points[layer] = self.graffiti_reference_points[layer]+[point[:]] if layer in self.graffiti_reference_points else [point]
					else :
						self.error(_("Warning! Found bad graffiti reference point in '%s' layer. Resulting Gcode could be corrupt!") % layer.get(inkex.addNS('label','inkscape')), "bad_orientation_points_in_some_layers") 
				
				elif i.tag == inkex.addNS('path','svg'):
					if "gcodetools"  not in i.keys() :
						self.paths[layer] = self.paths[layer] + [i] if layer in self.paths else [i]  
						if i.get("id") in self.selected :
							self.selected_paths[layer] = self.selected_paths[layer] + [i] if layer in self.selected_paths else [i]  

				elif i.get("gcodetools") == "In-out reference point group" :
					items_ = i.getchildren()
					items_.reverse()
					for j in items_ :
						if j.get("gcodetools") == "In-out reference point" :
							self.in_out_reference_points.append( self.apply_transforms(j,cubicsuperpath.parsePath(j.get("d")))[0][0][1] )


				elif i.tag == inkex.addNS("g",'svg'):
					recursive_search(i,layer, (i.get("id") in self.selected) )

				elif i.get("id") in self.selected :
# xgettext:no-pango-format
					self.error(_("This extension works with Paths and Dynamic Offsets and groups of them only! All other objects will be ignored!\nSolution 1: press Path->Object to path or Shift+Ctrl+C.\nSolution 2: Path->Dynamic offset or Ctrl+J.\nSolution 3: export all contours to PostScript level 2 (File->Save As->.ps) and File->Import this file."),"selection_contains_objects_that_are_not_paths")
				
					
		recursive_search(self.document.getroot(),self.document.getroot())

		if len(self.layers) == 1 : 
			self.error(_("Document has no layers! Add at least one layer using layers panel (Ctrl+Shift+L)"),"Error")
		root = self.document.getroot() 

		if  root in self.selected_paths or root in self.paths :
			self.error(_("Warning! There are some paths in the root of the document, but not in any layer! Using bottom-most layer for them."), "tools_warning" )

		if  root in self.selected_paths :
			if self.layers[-1] in self.selected_paths :
				self.selected_paths[self.layers[-1]] += self.selected_paths[root][:]
			else :	
				self.selected_paths[self.layers[-1]] = self.selected_paths[root][:]
			del self.selected_paths[root]
			
		if root in self.paths :	
			if self.layers[-1] in self.paths :
				self.paths[self.layers[-1]] += self.paths[root][:]
			else :
				self.paths[self.layers[-1]] = self.paths[root][:]
			del self.paths[root]


	def get_orientation_points(self,g):
		items = g.getchildren()
		items.reverse()
		p2, p3 = [], []
		p = None
		for i in items:
			if i.tag == inkex.addNS("g",'svg') and i.get("gcodetools") == "Gcodetools orientation point (2 points)":
				p2 += [i]
			if i.tag == inkex.addNS("g",'svg') and i.get("gcodetools") == "Gcodetools orientation point (3 points)":
				p3 += [i]
		if len(p2)==2 : p=p2 
		elif len(p3)==3 : p=p3 
		if p==None : return None
		points = []
		for i in p :	
			point = [[],[]]	
			for  node in i :
				if node.get('gcodetools') == "Gcodetools orientation point arrow":
					point[0] = self.apply_transforms(node,cubicsuperpath.parsePath(node.get("d")))[0][0][1]
				if node.get('gcodetools') == "Gcodetools orientation point text":
					r = re.match(r'(?i)\s*\(\s*(-?\s*\d*(?:,|\.)*\d*)\s*;\s*(-?\s*\d*(?:,|\.)*\d*)\s*;\s*(-?\s*\d*(?:,|\.)*\d*)\s*\)\s*',get_text(node))
					point[1] = [float(r.group(1)),float(r.group(2)),float(r.group(3))]
			if point[0]!=[] and point[1]!=[]:	points += [point]
		if len(points)==len(p2)==2 or len(points)==len(p3)==3 : return points
		else : return None
	
	def get_graffiti_reference_points(self,g):
			point = [[], '']
			for node in g :
				if node.get('gcodetools') == "Gcodetools graffiti reference point arrow":
					point[0] = self.apply_transforms(node,cubicsuperpath.parsePath(node.get("d")))[0][0][1]
				if node.get('gcodetools') == "Gcodetools graffiti reference point text":
					point[1] = get_text(node)
			if point[0]!=[] and point[1]!='' : return point
			else : return []

	def get_tool(self, g):
		tool = self.default_tool.copy()
		tool["self_group"] = g 
		for i in g:
			#	Get parameters
			if i.get("gcodetools") == "Gcodetools tool background" : 
				tool["style"] = simplestyle.parseStyle(i.get("style"))
			elif i.get("gcodetools") == "Gcodetools tool parameter" :
				key = None
				value = None
				for j in i:
					#need to recognise old tools from ver 1.6.04
					if j.get("gcodetools") == "Gcodetools tool definition field name" or j.get("gcodetools") == "Gcodetools tool defention field name":
						key = get_text(j)
					if j.get("gcodetools") == "Gcodetools tool definition field value" or j.get("gcodetools") == "Gcodetools tool defention field value":
						value = get_text(j)
						if value == "(None)": value = ""
				if value == None or key == None: continue
				#print_("Found tool parameter '%s':'%s'" % (key,value))
				if key in self.default_tool.keys() :
					 try :
						tool[key] = type(self.default_tool[key])(value)
					 except :
						tool[key] = self.default_tool[key]
						self.error(_("Warning! Tool's and default tool's parameter's (%s) types are not the same ( type('%s') != type('%s') ).") % (key, value, self.default_tool[key]), "tools_warning")
				else :
					tool[key] = value
					self.error(_("Warning! Tool has parameter that default tool has not ( '%s': '%s' ).") % (key, value), "tools_warning" )
		return tool
		
		
	def set_tool(self,layer):
#		print_(("index(layer)=",self.layers.index(layer),"set_tool():layer=",layer,"self.tools=",self.tools))
#		for l in self.layers:
#			print_(("l=",l))
		for i in range(self.layers.index(layer),-1,-1):
#			print_(("processing layer",i))
			if self.layers[i] in self.tools : 
				break
		if self.layers[i] in self.tools :
			if self.layers[i] != layer : self.tools[layer] = self.tools[self.layers[i]]
			if len(self.tools[layer])>1 : self.error(_("Layer '%s' contains more than one tool!") % self.layers[i].get(inkex.addNS('label','inkscape')), "more_than_one_tool")
			return self.tools[layer]
		else :
			self.error(_("Can not find tool for '%s' layer! Please add one with Tools library tab!") % layer.get(inkex.addNS('label','inkscape')), "no_tool_error")


################################################################################
###
###		Path to Gcode
###
################################################################################
	def path_to_gcode(self) :
		from functools import partial
		def get_boundaries(points):
			minx,miny,maxx,maxy=None,None,None,None
			out=[[],[],[],[]]
			for p in points:
				if minx==p[0]:
					out[0]+=[p]
				if minx==None or p[0]<minx: 
					minx=p[0]
					out[0]=[p]

				if miny==p[1]:
					out[1]+=[p]
				if miny==None or p[1]<miny: 
					miny=p[1]
					out[1]=[p]

				if maxx==p[0]:
					out[2]+=[p]
				if maxx==None or p[0]>maxx: 
					maxx=p[0]
					out[2]=[p]

				if maxy==p[1]:
					out[3]+=[p]
				if maxy==None or p[1]>maxy: 
					maxy=p[1]
					out[3]=[p]
			return out


		def remove_duplicates(points):
			i=0		
			out=[]
			for p in points:
				for j in xrange(i,len(points)):
					if p==points[j]: points[j]=[None,None]	
				if p!=[None,None]: out+=[p]
			i+=1
			return(out)
	
	
		def get_way_len(points):
			l=0
			for i in xrange(1,len(points)):
				l+=math.sqrt((points[i][0]-points[i-1][0])**2 + (points[i][1]-points[i-1][1])**2)
			return l

	
		def sort_dxfpoints(points):
			points=remove_duplicates(points)
#			print_(get_boundaries(get_boundaries(points)[2])[1])
			ways=[
						  # l=0, d=1, r=2, u=3
			 [3,0], # ul
			 [3,2], # ur
			 [1,0], # dl
			 [1,2], # dr
			 [0,3], # lu
			 [0,1], # ld
			 [2,3], # ru
			 [2,1], # rd
			]
#			print_(("points=",points))
			minimal_way=[]
			minimal_len=None
			minimal_way_type=None
			for w in ways:
				tpoints=points[:]
				cw=[]
#				print_(("tpoints=",tpoints))
				for j in xrange(0,len(points)):
					p=get_boundaries(get_boundaries(tpoints)[w[0]])[w[1]]
#					print_(p)
					tpoints.remove(p[0])
					cw+=p
				curlen = get_way_len(cw)
				if minimal_len==None or curlen < minimal_len: 
					minimal_len=curlen
					minimal_way=cw
					minimal_way_type=w
			
			return minimal_way

		def sort_lines(lines):
			if len(lines) == 0 : return []
			lines = [ [key]+lines[key] for key in range(len(lines))]			
			keys = [0]
			end_point = lines[0][3:]
			print_("!!!",lines,"\n",end_point)
			del lines[0]
			while len(lines)>0:
				dist = [ [point_to_point_d2(end_point,lines[i][1:3]),i] for i in range(len(lines))]
				i = min(dist)[1]
				keys.append(lines[i][0])
				end_point = lines[i][3:]
				del lines[i]
			return keys
			
		def sort_curves(curves):
			lines = []
			for curve in curves:
				lines += [curve[0][0][0] + curve[-1][-1][0]]
			return sort_lines(lines)
		
		def print_dxfpoints(points):
			gcode=""
			for point in points:
				gcode +="(drilling dxfpoint)\nG00 Z%f\nG00 X%f Y%f\nG01 Z%f F%f\nG04 P%f\nG00 Z%f\n" % (self.options.Zsafe,point[0],point[1],self.Zcoordinates[layer][1],self.tools[layer][0]["penetration feed"],0.2,self.options.Zsafe) 
#			print_(("got dxfpoints array=",points))
			return gcode
		
		def get_path_properties(node, recursive=True, tags={inkex.addNS('desc','svg'):"Description",inkex.addNS('title','svg'):"Title"} ) :
			res = {}
			done = False
			root = self.document.getroot()
			while not done and node != root :
				for i in node.getchildren():
					if i.tag in tags:
						res[tags[i.tag]] = i.text
					done = True	
				node =	node.getparent()
			return res

		if self.selected_paths == {} and self.options.auto_select_paths:
			paths=self.paths
			self.error(_("No paths are selected! Trying to work on all available paths."),"warning")
		else :
			paths = self.selected_paths
		self.check_dir() 
		gcode = ""
		
		biarc_group = inkex.etree.SubElement( self.selected_paths.keys()[0] if len(self.selected_paths.keys())>0 else self.layers[0], inkex.addNS('g','svg') )
		print_(("self.layers=",self.layers))
		print_(("paths=",paths))
		colors = {}
		for layer in self.layers :
			if layer in paths :
				print_(("layer",layer))
				# transform simple path to get all var about orientation
				self.transform_csp([ [ [[0,0],[0,0],[0,0]],  [[0,0],[0,0],[0,0]] ] ], layer)
			
				self.set_tool(layer)
				curves = []
				dxfpoints = []

				try :
					depth_func = eval('lambda c,d,s: ' + self.options.path_to_gcode_depth_function.strip('"'))				
				except:
					self.error("Bad depth function! Enter correct function at Path to Gcode tab!") 

				for path in paths[layer] :
					if "d" not in path.keys() : 
						self.error(_("Warning: One or more paths do not have 'd' parameter, try to Ungroup (Ctrl+Shift+G) and Object to Path (Ctrl+Shift+C)!"),"selection_contains_objects_that_are_not_paths")
						continue					
					csp = cubicsuperpath.parsePath(path.get("d"))
					csp = self.apply_transforms(path, csp)
					id_ = path.get("id")
					
					def set_comment(match, path):
						if match.group(1) in path.keys() :
							return path.get(match.group(1))
						else: 
							return "None"
					if self.options.comment_gcode != "" :
						comment = re.sub("\[([A-Za-z_\-\:]+)\]", partial(set_comment, path=path), self.options.comment_gcode)
						comment = comment.replace(":newline:","\n") 
						comment = gcode_comment_str(comment)
					else:
						comment = ""
					if self.options.comment_gcode_from_properties :
						tags = get_path_properties(path)
						for tag in tags :
							comment += gcode_comment_str("%s: %s"%(tag,tags[tag]))

					style = simplestyle.parseStyle(path.get("style"))
					colors[id_] = simplestyle.parseColor(style['stroke'] if "stroke"  in style and style['stroke']!='none' else "#000")
					if path.get("dxfpoint") == "1":
						tmp_curve=self.transform_csp(csp, layer)
						x=tmp_curve[0][0][0][0]
						y=tmp_curve[0][0][0][1]
						print_("got dxfpoint (scaled) at (%f,%f)" % (x,y))
						dxfpoints += [[x,y]]
					else:
						
						zd,zs = self.Zcoordinates[layer][1],	self.Zcoordinates[layer][0]
						c = 1. - float(sum(colors[id_]))/255/3
						curves += 	[
										 [  
										 	[id_, depth_func(c,zd,zs), comment],
										 	[ self.parse_curve([subpath], layer) for subpath in csp  ]
										 ]
									]
#				for c in curves : 
#					print_(c)
				dxfpoints=sort_dxfpoints(dxfpoints)
				gcode+=print_dxfpoints(dxfpoints)
				
				
				for curve in curves :
					for subcurve in curve[1] :
						self.draw_curve(subcurve, layer)
					
				if self.options.path_to_gcode_order == 'subpath by subpath':
					curves_ = []
					for curve in curves :
						curves_ += [ [curve[0],[subcurve]]  for subcurve in curve[1] ]  
					curves = curves_	

					self.options.path_to_gcode_order = 'path by path'
					
				if self.options.path_to_gcode_order == 'path by path':
					if self.options.path_to_gcode_sort_paths :
						keys = sort_curves( [curve[1] for curve in curves] )
					else :
						keys = range(len(curves))
					for key in keys:
						d = curves[key][0][1]
						for step in range( 0,  int(math.ceil( abs((zs-d)/self.tools[layer][0]["depth step"] )) ) ):
							z = max(d, zs - abs(self.tools[layer][0]["depth step"]*(step+1)))
							
							gcode += gcode_comment_str("\nStart cutting path id: %s"%curves[key][0][0])
							if curves[key][0][2] != "()" :
								gcode += curves[key][0][2] # add comment
								
							for curve in curves[key][1]:
								gcode += self.generate_gcode(curve, layer, z)
								
							gcode += gcode_comment_str("End cutting path id: %s\n\n"%curves[key][0][0])
							
				else:	# pass by pass
					mind = min( [curve[0][1] for curve in curves] )	
					for step in range( 0,  int(math.ceil( abs((zs-mind)/self.tools[layer][0]["depth step"] )) ) ):
						z = zs - abs(self.tools[layer][0]["depth step"]*(step))
						curves_ = []
						for curve in curves:
							if curve[0][1]<z : 
								curves_.append(curve)

						z = zs - abs(self.tools[layer][0]["depth step"]*(step+1))
						gcode += "\n(Pass at depth %s)\n"%z

						if self.options.path_to_gcode_sort_paths :
							keys = sort_curves( [curve[1] for curve in curves_] )		
						else :
							keys = range(len(curves_))
						for key in keys:
				
							gcode += gcode_comment_str("Start cutting path id: %s"%curves[key][0][0])
							if curves[key][0][2] != "()" :
								gcode += curves[key][0][2] # add comment

							for subcurve in curves_[key][1]:
								gcode += self.generate_gcode(subcurve, layer, max(z,curves_[key][0][1]))
				
							gcode += gcode_comment_str("End cutting path id: %s\n\n"%curves[key][0][0])

		self.export_gcode(gcode,comments=self.tools[layer][0]["comments"])
	
################################################################################
###
###		dxfpoints
###
################################################################################
	def dxfpoints(self):
		if self.selected_paths == {}:
			self.error(_("Noting is selected. Please select something to convert to drill point (dxfpoint) or clear point sign."),"warning")
		for layer in self.layers :
			if layer in self.selected_paths :
				for path in self.selected_paths[layer]:
#					print_(("processing path",path.get('d')))
					if self.options.dxfpoints_action == 'replace':
#						print_("trying to set as dxfpoint")
						
						path.set("dxfpoint","1")
						r = re.match("^\s*.\s*(\S+)",path.get("d"))
						if r!=None:
							print_(("got path=",r.group(1)))
							path.set("d","m %s 2.9375,-6.343750000001 0.8125,1.90625 6.843748640396,-6.84374864039 0,0 0.6875,0.6875 -6.84375,6.84375 1.90625,0.812500000001 z" % r.group(1))
							path.set("style",styles["dxf_points"])

					if self.options.dxfpoints_action == 'save':
						path.set("dxfpoint","1")

					if self.options.dxfpoints_action == 'clear' and path.get("dxfpoint") == "1":
						path.set("dxfpoint","0")
#						for id, node in self.selected.iteritems():
#							print_((id,node,node.attrib))


################################################################################
###
###		Artefacts
###
################################################################################
	def area_artefacts(self) :
			if self.selected_paths == {} and self.options.auto_select_paths:
				paths=self.paths
				self.error(_("No paths are selected! Trying to work on all available paths."),"warning")
			else :
				paths = self.selected_paths
			for layer in paths :
#				paths[layer].reverse() # Reverse list of paths to leave their order 
				for path in paths[layer] :
					parent = path.getparent()
					style = path.get("style") if "style" in path.keys() else ""
					if "d" not in path.keys() : 
						self.error(_("Warning: One or more paths do not have 'd' parameter, try to Ungroup (Ctrl+Shift+G) and Object to Path (Ctrl+Shift+C)!"),"selection_contains_objects_that_are_not_paths")
						continue		
					csp = cubicsuperpath.parsePath(path.get("d"))
					remove = []
					for i in range(len(csp)) :
						subpath = [ [point[:] for point in points] for points in csp[i]]
						subpath = self.apply_transforms(path,[subpath])[0]
						bounds = csp_simple_bound([subpath])
						if  (bounds[2]-bounds[0])**2+(bounds[3]-bounds[1])**2 < self.options.area_find_artefacts_diameter**2:
							if self.options.area_find_artefacts_action == "mark with an arrow" :
								arrow =  cubicsuperpath.parsePath( 'm %s,%s 2.9375,-6.343750000001 0.8125,1.90625 6.843748640396,-6.84374864039 0,0 0.6875,0.6875 -6.84375,6.84375 1.90625,0.812500000001 z' % (subpath[0][1][0],subpath[0][1][1]) )
 								arrow = self.apply_transforms(path,arrow,True)
								inkex.etree.SubElement(parent, inkex.addNS('path','svg'), 
										{
											'd': cubicsuperpath.formatPath(arrow),
											'style': styles["area artefact arrow"],
											'gcodetools': 'area artefact arrow',
										})
							elif self.options.area_find_artefacts_action == "mark with style" :
								inkex.etree.SubElement(parent, inkex.addNS('path','svg'), {'d': cubicsuperpath.formatPath(csp[i]), 'style': styles["area artefact"]})
								remove.append(i)
							elif self.options.area_find_artefacts_action == "delete" :
								remove.append(i)
								print_("Deleted artefact %s" % subpath )
					remove.reverse()
					for i in remove :
						del csp[i]
					if len(csp) == 0 :	
						parent.remove(path)
					else :
						path.set("d", cubicsuperpath.formatPath(csp))
							
			return
			

################################################################################
###
###		Calculate area curves
###
################################################################################
	def area(self) :
		if len(self.selected_paths)<=0:
			self.error(_("This extension requires at least one selected path."),"warning")
			return
		for layer in self.layers :
			if layer in self.selected_paths :
				self.set_tool(layer)
				if self.tools[layer][0]['diameter']<=0 : 
					self.error(_("Tool diameter must be > 0 but tool's diameter on '%s' layer is not!") % layer.get(inkex.addNS('label','inkscape')),"area_tools_diameter_error")
	
				for path in self.selected_paths[layer]:
					print_(("doing path",	path.get("style"), path.get("d")))

					area_group = inkex.etree.SubElement( path.getparent(), inkex.addNS('g','svg') )
				
					d = path.get('d')
					print_(d)
					if d==None:
						print_("omitting non-path")
						self.error(_("Warning: omitting non-path"),"selection_contains_objects_that_are_not_paths")
						continue
					csp = cubicsuperpath.parsePath(d)
				
					if path.get(inkex.addNS('type','sodipodi'))!="inkscape:offset":
						print_("Path %s is not an offset. Preparation started." % path.get("id"))
						# Path is not offset. Preparation will be needed.
						# Finding top most point in path (min y value)
						
						min_x,min_y,min_i,min_j,min_t = csp_true_bounds(csp)[1]
						
						# Reverse path if needed.
						if min_y!=float("-inf") :
							# Move outline subpath to the begining of csp
	 					 	subp = csp[min_i]
	 					 	del csp[min_i]
	 					 	j = min_j
	 					 	# Split by the topmost point and join again
	 					 	if min_t in [0,1]:
	 					 		if min_t == 0: j=j-1
		 					 	subp[-1][2], subp[0][0] = subp[-1][1], subp[0][1]
	 					 		subp = [ [subp[j][1], subp[j][1], subp[j][2]] ] + subp[j+1:] + subp[:j] + [ [subp[j][0], subp[j][1], subp[j][1]] ]
							else: 					 		
		 						sp1,sp2,sp3 = csp_split(subp[j-1],subp[j],min_t)
		 						subp[-1][2], subp[0][0] = subp[-1][1], subp[0][1]
								subp = [ [ sp2[1], sp2[1],sp2[2] ] ] + [sp3] + subp[j+1:] + subp[:j-1] + [sp1] + [[ sp2[0], sp2[1],sp2[1] ]] 					 	  
	 					 	csp = [subp] + csp
							# reverse path if needed
							if csp_subpath_ccw(csp[0]) :
								for i in range(len(csp)):
								 	n = []
								 	for j in csp[i]:
								 		n = [  [j[2][:],j[1][:],j[0][:]]  ] + n
								 	csp[i] = n[:]

	 					 	
						d = cubicsuperpath.formatPath(csp)
						print_(("original  d=",d))
						d = re.sub(r'(?i)(m[^mz]+)',r'\1 Z ',d)
						d = re.sub(r'(?i)\s*z\s*z\s*',r' Z ',d)
						d = re.sub(r'(?i)\s*([A-Za-z])\s*',r' \1 ',d)
						print_(("formatted d=",d))
					# scale = sqrt(Xscale**2 + Yscale**2) / sqrt(1**2 + 1**2)
					p0 = self.transform([0,0],layer)
					p1 = self.transform([0,1],layer)
					scale = (P(p0)-P(p1)).mag()
					if scale == 0 : scale = 1. 
					else : scale = 1./scale
					print_(scale)
					tool_d = self.tools[layer][0]['diameter']*scale
					r = self.options.area_inkscape_radius * scale
					sign=1 if r>0 else -1
					print_("Tool diameter = %s, r = %s" % (tool_d, r))
					
					# avoiding infinite loops
					if self.options.area_tool_overlap>0.9 : self.options.area_tool_overlap = .9
			
					for i in range(self.options.max_area_curves):
						radius = - tool_d * (i*(1-self.options.area_tool_overlap)+0.5) * sign
						if abs(radius)>abs(r): 
							radius = -r
						
						inkex.etree.SubElement(	area_group, inkex.addNS('path','svg'), 
										{
											 inkex.addNS('type','sodipodi'):	'inkscape:offset',
											 inkex.addNS('radius','inkscape'):	str(radius),
											 inkex.addNS('original','inkscape'):	d,
											'style': styles["biarc_style_i"]['area']
										})
						print_(("adding curve",area_group,d,styles["biarc_style_i"]['area']))
						if radius == -r : break 


################################################################################
###
###		Polyline to biarc
###
###		Converts Polyline to Biarc
################################################################################
	def polyline_to_biarc(self):
		
		
		
		def biarc(sm, depth=0):
			def biarc_split(sp1,sp2, z1, z2, depth): 
				if depth<options.biarc_max_split_depth:
					sp1,sp2,sp3 = csp_split(sp1,sp2)
					l1, l2 = cspseglength(sp1,sp2), cspseglength(sp2,sp3)
					if l1+l2 == 0 : zm = z1
					else : zm = z1+(z2-z1)*l1/(l1+l2)
					return biarc(sp1,sp2,z1,zm,depth+1)+biarc(sp2,sp3,zm,z2,depth+1)
				else: return [ [sp1[1],'line', 0, 0, sp2[1], [z1,z2]] ]

			P0, P4 = P(sp1[1]), P(sp2[1])
			TS, TE, v = (P(sp1[2])-P0), -(P(sp2[0])-P4), P0 - P4
			tsa, tea, va = TS.angle(), TE.angle(), v.angle()
			if TE.mag()<straight_distance_tolerance and TS.mag()<straight_distance_tolerance:	
				# Both tangents are zerro - line straight
				return [ [sp1[1],'line', 0, 0, sp2[1], [z1,z2]] ]
			if TE.mag() < straight_distance_tolerance:
				TE = -(TS+v).unit()
				r = TS.mag()/v.mag()*2
			elif TS.mag() < straight_distance_tolerance:
				TS = -(TE+v).unit()
				r = 1/( TE.mag()/v.mag()*2 )
			else:	
				r=TS.mag()/TE.mag()
			TS, TE = TS.unit(), TE.unit()
			tang_are_parallel = ((tsa-tea)%math.pi<straight_tolerance or math.pi-(tsa-tea)%math.pi<straight_tolerance )
			if ( tang_are_parallel  and 
						((v.mag()<straight_distance_tolerance or TE.mag()<straight_distance_tolerance or TS.mag()<straight_distance_tolerance) or
							1-abs(TS*v/(TS.mag()*v.mag()))<straight_tolerance)	):
						# Both tangents are parallel and start and end are the same - line straight
						# or one of tangents still smaller then tollerance

						# Both tangents and v are parallel - line straight
				return [ [sp1[1],'line', 0, 0, sp2[1], [z1,z2]] ]

			c,b,a = v*v, 2*v*(r*TS+TE), 2*r*(TS*TE-1)
			if v.mag()==0:
				return biarc_split(sp1, sp2, z1, z2, depth)
			asmall, bsmall, csmall = abs(a)<10**-10,abs(b)<10**-10,abs(c)<10**-10 
			if 		asmall and b!=0:	beta = -c/b
			elif 	csmall and a!=0:	beta = -b/a 
			elif not asmall:	 
				discr = b*b-4*a*c
				if discr < 0:	raise ValueError, (a,b,c,discr)
				disq = discr**.5
				beta1 = (-b - disq) / 2 / a
				beta2 = (-b + disq) / 2 / a
				if beta1*beta2 > 0 :	raise ValueError, (a,b,c,disq,beta1,beta2)
				beta = max(beta1, beta2)
			elif	asmall and bsmall:	
				return biarc_split(sp1, sp2, z1, z2, depth)
			alpha = beta * r
			ab = alpha + beta 
			P1 = P0 + alpha * TS
			P3 = P4 - beta * TE
			P2 = (beta / ab)  * P1 + (alpha / ab) * P3


			def calculate_arc_params(P0,P1,P2):
				D = (P0+P2)/2
				if (D-P1).mag()==0: return None, None
				R = D - ( (D-P0).mag()**2/(D-P1).mag() )*(P1-D).unit()
				p0a, p1a, p2a = (P0-R).angle()%(2*math.pi), (P1-R).angle()%(2*math.pi), (P2-R).angle()%(2*math.pi)
				alpha =  (p2a - p0a) % (2*math.pi)					
				if (p0a<p2a and  (p1a<p0a or p2a<p1a))	or	(p2a<p1a<p0a) : 
					alpha = -2*math.pi+alpha 
				if abs(R.x)>1000000 or abs(R.y)>1000000  or (R-P0).mag<options.min_arc_radius**2 :
					return None, None
				else :	
					return  R, alpha
			R1,a1 = calculate_arc_params(P0,P1,P2)
			R2,a2 = calculate_arc_params(P2,P3,P4)
			if R1==None or R2==None or (R1-P0).mag()<straight_tolerance or (R2-P2).mag()<straight_tolerance	: return [ [sp1[1],'line', 0, 0, sp2[1], [z1,z2]] ]
	
			d = csp_to_arc_distance(sp1,sp2, [P0,P2,R1,a1],[P2,P4,R2,a2])
			if d > options.biarc_tolerance and depth<options.biarc_max_split_depth	 : return biarc_split(sp1, sp2, z1, z2, depth)
			else:
				if R2.mag()*a2 == 0 : zm = z2
				else : zm  = z1 + (z2-z1)*(abs(R1.mag()*a1))/(abs(R2.mag()*a2)+abs(R1.mag()*a1)) 

				l = (P0-P2).l2()
				if  l < EMC_TOLERANCE_EQUAL**2 or l<EMC_TOLERANCE_EQUAL**2 * R1.l2() /100 :
					# arc should be straight otherwise it could be threated as full circle
					arc1 = [ sp1[1], 'line', 0, 0, [P2.x,P2.y], [z1,zm] ] 
				else :
					arc1 = [ sp1[1], 'arc', [R1.x,R1.y], a1, [P2.x,P2.y], [z1,zm] ] 

				l = (P4-P2).l2()
				if  l < EMC_TOLERANCE_EQUAL**2 or l<EMC_TOLERANCE_EQUAL**2 * R2.l2() /100 :
					# arc should be straight otherwise it could be threated as full circle
					arc2 = [ [P2.x,P2.y], 'line', 0, 0, [P4.x,P4.y], [zm,z2] ] 
				else :
					arc2 = [ [P2.x,P2.y], 'arc', [R2.x,R2.y], a2, [P4.x,P4.y], [zm,z2] ]
		
				return [ arc1, arc2 ]

		
		
		
		
		for layer in self.layers :
			if layer in self.selected_paths :
				for path in self.selected_paths[layer]:
					d = path.get('d')
					if d==None:
						print_("omitting non-path")
						self.error(_("Warning: omitting non-path"),"selection_contains_objects_that_are_not_paths")
						continue
					csp = cubicsuperpath.parsePath(d)
					csp = self.apply_transforms(path, csp)
					csp = self.transform_csp(csp, layer)
					
					# lets pretend that csp is a polyline 
					poly = [ [point[1] for point in subpath] for subpath in csp ]
					
					self.draw_csp([ [ [point,point,point] for point in subpoly] for subpoly in poly ],layer)
					
					# lets create biarcs 
					for subpoly in poly :
						# lets split polyline into different smooth parths. 
						
						if len(subpoly)>2 :
							smooth = [ [subpoly[0],subpoly[1]] ]
							for p1,p2,p3 in zip(subpoly,subpoly[1:],subpoly[2:]) :
								# normalize p1p2 and p2p3 to get angle
								s1,s2 = normalize( p1[0]-p2[0], p1[1]-p2[1]), normalize( p3[0]-p2[0], p3[1]-p2[1]) 
								if cross(s1,s2) > corner_tolerance :
									#it's an angle 
									smooth += [  [p2,p3]  ]
								else: 
									smooth[-1].append(p3)							
							for sm in smooth :
								smooth_polyline_to_biarc(sm)	

################################################################################
###
###		Area fill 
###
###		Fills area with lines
################################################################################


	def area_fill(self):
		# convert degrees into rad
		self.options.area_fill_angle = self.options.area_fill_angle * math.pi / 180
		if len(self.selected_paths)<=0:
			self.error(_("This extension requires at least one selected path."),"warning")
			return
		for layer in self.layers :
			if layer in self.selected_paths :
				self.set_tool(layer)
				if self.tools[layer][0]['diameter']<=0 : 
					self.error(_("Tool diameter must be > 0 but tool's diameter on '%s' layer is not!") % layer.get(inkex.addNS('label','inkscape')),"area_tools_diameter_error")
				tool = self.tools[layer][0]
				for path in self.selected_paths[layer]:
					lines = []
					print_(("doing path",	path.get("style"), path.get("d")))
					area_group = inkex.etree.SubElement( path.getparent(), inkex.addNS('g','svg') )
					d = path.get('d')
					if d==None:
						print_("omitting non-path")
						self.error(_("Warning: omitting non-path"),"selection_contains_objects_that_are_not_paths")
						continue
					csp = cubicsuperpath.parsePath(d)
					csp = self.apply_transforms(path, csp)
					csp = csp_close_all_subpaths(csp)
					csp = self.transform_csp(csp, layer)
					#maxx = max([x,y,i,j,root],maxx)
					
					# rotate the path to get bounds in defined direction.
					a = - self.options.area_fill_angle
					rotated_path = [   [ [ [point[0]*math.cos(a) - point[1]*math.sin(a), point[0]*math.sin(a)+point[1]*math.cos(a)]  for point in sp] for sp in subpath] for subpath in csp  ]
					bounds =  csp_true_bounds(rotated_path)
					
					# Draw the lines 
					# Get path's bounds
					b = [0.0, 0.0, 0.0, 0.0] # [minx,miny,maxx,maxy]
					for k in range(4):
						i, j, t = bounds[k][2], bounds[k][3], bounds[k][4]
						b[k] = csp_at_t(rotated_path[i][j-1],rotated_path[i][j],t)[k%2]

						
					# Zig-zag
					r = tool['diameter']*(1-self.options.area_tool_overlap)
					if r<=0 :
						self.error('Tools diameter must be greater than 0!', 'error')
						return

					lines += [ [] ]

					if self.options.area_fill_method == 'zig-zag' :
						i = b[0] - self.options.area_fill_shift*r
						top = True
						last_one = True
						while (i<b[2] or last_one) : 
							if i>=b[2] : last_one = False
							if lines[-1] == [] :
								lines[-1] += [  [i,b[3]]  ]

							if top :
								lines[-1] += [ [i,b[1]],[i+r,b[1]] ]

							else :
									lines[-1] += [ [i,b[3]], [i+r,b[3]] ]

							top = not top
							i += r
					else :
					
						w, h  = b[2]-b[0] + self.options.area_fill_shift*r , b[3]-b[1] +  self.options.area_fill_shift*r
						x,y = b[0] - self.options.area_fill_shift*r, b[1] - self.options.area_fill_shift*r
						lines[-1] += [  [x,y] ]
						stage = 0
						start = True
						while w>0 and h>0 :
							stage = (stage+1)%4
							if   stage == 0 :
								y -= h
								h -= r
							elif stage == 1:
								x += w
								if not start:
									w -= r
								start = False	
							elif stage == 2 :
								y += h
								h -= r
							elif stage == 3:
								x -= w
								w -=r
							
							lines[-1] += [ [x,y] ]

						stage = (stage+1)%4							
						if w <= 0 and h>0 :
							y = y-h if stage == 0 else y+h  
						if h <= 0  and w>0 :
							x = x-w if stage == 3 else x+w  
						lines[-1] += [ [x,y] ]
					# Rotate created paths back
					a =  self.options.area_fill_angle
					lines = [ [ [point[0]*math.cos(a) - point[1]*math.sin(a), point[0]*math.sin(a)+point[1]*math.cos(a)] for point in subpath] for subpath in lines  ]

					# get the intersection points
					
					splitted_line = [ [lines[0][0]] ]
					intersections = {}
					for l1,l2, in zip(lines[0],lines[0][1:]): 
						ints = []
						
						if l1[0]==l2[0] and l1[1]==l2[1] : continue
						for i in range(len(csp)) :
							for j in range(1,len(csp[i]))  :
								sp1,sp2 = csp[i][j-1], csp[i][j]
								roots = csp_line_intersection(l1,l2,sp1,sp2)
								for t in roots :
									p = tuple(csp_at_t(sp1,sp2,t))
									if l1[0]==l2[0] :
										t1 = (p[1]-l1[1])/(l2[1]-l1[1])
									else :
										t1 = (p[0]-l1[0])/(l2[0]-l1[0])
									if 0<=t1<=1	:
										ints += [[t1, p[0],p[1], i,j,t]]
										if p in intersections :
											intersections[p]  += [ [i,j,t] ]  
										else : 	
											intersections[p]  = [ [i,j,t] ]  
										#p = self.transform(p,layer,True)
										#draw_pointer(p)
						ints.sort()
						for i in ints:
							splitted_line[-1] +=[ [ i[1], i[2]] ]
							splitted_line += [ [ [ i[1], i[2]] ] ]
						splitted_line[-1] += [  l2  ]
						i = 0
					print_(splitted_line)
					while i < len(splitted_line) :
						# check if the middle point of the first lines segment is inside the path.
						# and remove the subline if not.
						l1,l2 = splitted_line[i][0],splitted_line[i][1]
						p = [(l1[0]+l2[0])/2, (l1[1]+l2[1])/2]
						if not point_inside_csp(p, csp):
							#i +=1 						
							del splitted_line[i]
						else :
							i += 1
					
					
					
					# if we've used spiral method we'll try to save the order of cutting
					do_not_change_order = self.options.area_fill_method == 'spiral' 
					# now let's try connect splitted lines
					#while len(splitted_line)>0 :
					#TODO	
					
					# and apply back transrormations to draw them
					csp_line = csp_from_polyline(splitted_line)
					csp_line = self.transform_csp(csp_line, layer, True)
					
					self.draw_csp(csp_line, group = area_group)
#					draw_csp(lines)
					


					 					


################################################################################
###
###		Engraving
###
#LT Notes to self: See wiki.inkscape.org/wiki/index.php/PythonEffectTutorial
# To create anything in the Inkscape document, look at the XML editor for
# details of how such an element looks in XML, then follow this model.
#layer number n appears in XML as <svg:g id="layern" inkscape:label="layername">
#
#to create it, use
#Mylayer=inkex.etree.SubElement(self.document.getroot(), 'g') #Create a generic element
#Mylayer.set(inkex.addNS('label', 'inkscape'), "layername")   #Gives it a name
#Mylayer.set(inkex.addNS('groupmode', 'inkscape'), 'layer')   #Tells Inkscape it's a layer
#
#group appears in XML as <svg:g id="gnnnnn"> where nnnnn is a number
#
#to create it, use
#Mygroup=inkex.etree.SubElement(parent, inkex.addNS('g','svg'), {"gcodetools":"My group label"})
# where parent may be the layer or a parent group. To get the parent group, you can use
#parent = self.selected_paths[layer][0].getparent()
################################################################################
	def engraving(self) :
		#global x1,y1,rx,ry
		global cspm, wl
		global nlLT, i, j
		global gcode_3Dleft ,gcode_3Dright
		global max_dist #minimum of tool radius and user's requested maximum distance
		global eye_dist
		eye_dist = 100 #3D constant. Try varying it for your eyes


		def bisect((nx1,ny1),(nx2,ny2)) :
			"""LT Find angle bisecting the normals n1 and n2

			Parameters: Normalised normals
			Returns: nx - Normal of bisector, normalised to 1/cos(a)
				   ny -
				   sinBis2 - sin(angle turned/2): positive if turning in
			Note that bisect(n1,n2) and bisect(n2,n1) give opposite sinBis2 results
			If sinturn is less than the user's requested angle tolerance, I return 0
			"""
			#We can get absolute value of cos(bisector vector)
			#Note: Need to use max in case of rounding errors
			cosBis = math.sqrt(max(0,(1.0+nx1*nx2-ny1*ny2)/2.0))
			#We can get correct sign of the sin, assuming cos is positive
			if (abs(ny1-ny2)< engraving_tolerance)  or (abs(cosBis) < engraving_tolerance) :
				if (abs(nx1-nx2)< engraving_tolerance): return(nx1,ny1,0.0)
				sinBis = math.copysign(1,ny1)
			else :
				sinBis = cosBis*(nx2-nx1)/(ny1-ny2)
			#We can correct signs by noting that the dot product
			# of bisector and either normal must be >0
			costurn=cosBis*nx1+sinBis*ny1
			if costurn == 0 : return (ny1*100,-nx1*100,1) #Path doubles back on itself
			sinturn=sinBis*nx1-cosBis*ny1
			if costurn<0 :  sinturn=-sinturn
			if 0 < sinturn*114.6 < (180-self.options.engraving_sharp_angle_tollerance) :
				sinturn=0 #set to zero if less than the user wants to see.
			return (cosBis/costurn,sinBis/costurn, sinturn)
			#end bisect

		def get_radius_to_line((x1,y1),(nx1,ny1), (nx2,ny2),(x2,y2),(nx23,ny23),(x3,y3),(nx3,ny3)):
			"""LT find biggest circle we can engrave here, if constrained by line 2-3

			Parameters:
				x1,y1,nx1,ny1 coordinates and normal of the line we're currently engraving
				nx2,ny2 angle bisector at point 2
				x2,y2 coordinates of first point of line 2-3
				nx23,ny23 normal to the line 2-3
				x3,y3 coordinates of the other end
				nx3,ny3 angle bisector at point 3
			Returns:
				radius or self.options.engraving_max_dist if line doesn't limit radius
			This function can be used in three ways:
			- With nx1=ny1=0 it finds circle centred at x1,y1
			- with nx1,ny1 normalised, it finds circle tangential at x1,y1
			- with nx1,ny1 scaled by 1/cos(a) it finds circle centred on an angle bisector
				 where a is the angle between the bisector and the previous/next normals

			If the centre of the circle tangential to the line 2-3 is outside the
			angle bisectors at its ends, ignore this line. 

			# Note that it handles corners in the conventional manner of letter cutting
			# by mitering, not rounding.
			# Algorithm uses dot products of normals to find radius
			# and hence coordinates of centre
			"""

			global max_dist

			#Start by converting coordinates to be relative to x1,y1
			x2,y2= x2-x1, y2-y1
			x3,y3= x3-x1, y3-y1

			#The logic uses vector arithmetic.
			#The dot product of two vectors gives the product of their lengths
			#multiplied by the cos of the angle between them.
			# So, the perpendicular distance from x1y1 to the line 2-3
			# is equal to the dot product of its normal and x2y2 or x3y3
			#It is also equal to the projection of x1y1-xcyc on the line's normal
			# plus the radius. But, as the normal faces inside the path we must negate it.

			#Make sure the line in question is facing x1,y1 and vice versa
			dist=-x2*nx23-y2*ny23
			if dist<0 : return max_dist
			denom=1.-nx23*nx1-ny23*ny1
			if denom < engraving_tolerance : return max_dist

			#radius and centre are:
			r=dist/denom
			cx=r*nx1
			cy=r*ny1
			#if c is not between the angle bisectors at the ends of the line, ignore
			#Use vector cross products. Not sure if I need the .0001 safety margins:
			if (x2-cx)*ny2 > (y2-cy)*nx2 +0.0001 :
				return max_dist 
			if (x3-cx)*ny3 < (y3-cy)*nx3  -0.0001 :
				return max_dist 
			return min(r, max_dist)
			#end of get_radius_to_line

		def get_radius_to_point((x1,y1),(nx,ny), (x2,y2)):
			"""LT find biggest circle we can engrave here, constrained by point x2,y2

			This function can be used in three ways:
			- With nx=ny=0 it finds circle centred at x1,y1
			- with nx,ny normalised, it finds circle tangential at x1,y1
			- with nx,ny scaled by 1/cos(a) it finds circle centred on an angle bisector
				 where a is the angle between the bisector and the previous/next normals

			Note that I wrote this to replace find_cutter_centre. It is far less
			sophisticated but, I hope, far faster.
			It turns out that finding a circle touching a point is harder than a circle
			touching a line.
			"""

			global max_dist

			#Start by converting coordinates to be relative to x1,y1
			x2,y2= x2-x1, y2-y1
			denom=nx**2+ny**2-1
			if denom<=engraving_tolerance : #Not a corner bisector
				if denom==-1 : #Find circle centre x1,y1
					return math.sqrt(x2**2+y2**2)
				#if x2,y2 not in front of the normal...
				if x2*nx+y2*ny <=0 : return max_dist
				#print_("Straight",x1,y1,nx,ny,x2,y2)
				return (x2**2+y2**2)/(2*(x2*nx+y2*ny) )
			#It is a corner bisector, so..
			discriminator = (x2*nx+y2*ny)**2 - denom*(x2**2+y2**2)
			if discriminator < 0 :
				return max_dist #this part irrelevant
			r=(x2*nx+y2*ny -math.sqrt(discriminator))/denom
			#print_("Corner",x1,y1,nx,ny,x1+x2,y1+y2,discriminator,r)
			return min(r, max_dist)
			#end of get_radius_to_point

		def bez_divide(a,b,c,d):
			"""LT recursively divide a Bezier.

			Divides until difference between each
			part and a straight line is less than some limit
			Note that, as simple as this code is, it is mathematically correct.
			Parameters:
				a,b,c and d are each a list of x,y real values
				Bezier end points a and d, control points b and c
			Returns:
				a list of Beziers.
					Each Bezier is a list with four members,
						each a list holding a coordinate pair
				Note that the final point of one member is the same as
				the first point of the next, and the control points
				there are smooth and symmetrical. I use this fact later.
			"""
			bx=b[0]-a[0]
			by=b[1]-a[1]
			cx=c[0]-a[0]
			cy=c[1]-a[1]
			dx=d[0]-a[0]
			dy=d[1]-a[1]
			limit=8*math.hypot(dx,dy)/self.options.engraving_newton_iterations
			#LT This is the only limit we get from the user currently
			if abs(dx*by-bx*dy)<limit and abs(dx*cy-cx*dy)<limit :
				return [[a,b,c,d]]
			abx=(a[0]+b[0])/2.0
			aby=(a[1]+b[1])/2.0
			bcx=(b[0]+c[0])/2.0
			bcy=(b[1]+c[1])/2.0
			cdx=(c[0]+d[0])/2.0
			cdy=(c[1]+d[1])/2.0
			abcx=(abx+bcx)/2.0
			abcy=(aby+bcy)/2.0
			bcdx=(bcx+cdx)/2.0
			bcdy=(bcy+cdy)/2.0
			m=[(abcx+bcdx)/2.0,(abcy+bcdy)/2.0]
			return bez_divide(a,[abx,aby],[abcx,abcy],m) + bez_divide(m,[bcdx,bcdy],[cdx,cdy],d)
			#end of bez_divide

		def get_biggest((x1,y1),(nx,ny)):
			"""LT Find biggest circle we can draw inside path at point x1,y1 normal nx,ny

			Parameters:
				point - either on a line or at a reflex corner
				normal - normalised to 1 if on a line, to 1/cos(a) at a corner
			Returns:
				tuple (j,i,r)
				..where j and i are indices of limiting segment, r is radius
			"""
			global max_dist, nlLT, i, j
			n1 = nlLT[j][i-1] #current node
			jjmin = -1
			iimin = -1
			r = max_dist
			# set limits within which to look for lines
			xmin, xmax = x1+r*nx-r, x1+r*nx+r
			ymin, ymax = y1+r*ny-r, y1+r*ny+r
			for jj in xrange(0,len(nlLT)) : #for every subpath of this object
				for ii in xrange(0,len(nlLT[jj])) : #for every point and line
					if nlLT[jj][ii-1][2] : #if a point
						if jj==j : #except this one
							if abs(ii-i)<3 or abs(ii-i)>len(nlLT[j])-3 : continue
						t1=get_radius_to_point((x1,y1),(nx,ny),nlLT[jj][ii-1][0] )
						#print_("Try pt   i,ii,t1,x1,y1",i,ii,t1,x1,y1)
					else: #doing a line
						if jj==j : #except this one
							if abs(ii-i)<2 or abs(ii-i)==len(nlLT[j])-1 : continue
							if abs(ii-i)==2  and nlLT[j][(ii+i)/2-1][3]<=0 : continue
							if (abs(ii-i)==len(nlLT[j])-2) and nlLT[j][-1][3]<=0 : continue
						nx2,ny2 = nlLT[jj][ii-2][1]
						x2,y2 = nlLT[jj][ii-1][0]
						nx23,ny23 = nlLT[jj][ii-1][1]
						x3,y3 = nlLT[jj][ii][0]
						nx3,ny3 = nlLT[jj][ii][1]
						if nlLT[jj][ii-2][3]>0 : #acute, so use normal, not bisector
							nx2=nx23
							ny2=ny23
						if nlLT[jj][ii][3]>0 : #acute, so use normal, not bisector
							nx3=nx23
							ny3=ny23
						x23min,x23max=min(x2,x3),max(x2,x3)
						y23min,y23max=min(y2,y3),max(y2,y3)
						#see if line in range
						if n1[2]==False and (x23max<xmin or x23min>xmax or y23max<ymin or y23min>ymax) : continue
						t1=get_radius_to_line((x1,y1),(nx,ny), (nx2,ny2),(x2,y2),(nx23,ny23), (x3,y3),(nx3,ny3))
						#print_("Try line i,ii,t1,x1,y1",i,ii,t1,x1,y1)
					if 0<=t1<r :
						r = t1
						iimin = ii
						jjmin = jj
						xmin, xmax = x1+r*nx-r, x1+r*nx+r
						ymin, ymax = y1+r*ny-r, y1+r*ny+r
				#next ii
			#next jj
			return (jjmin,iimin,r)
			#end of get_biggest

		def line_divide((x0,y0),j0,i0,(x1,y1),j1,i1,(nx,ny),length):
			"""LT recursively divide a line as much as necessary

			NOTE: This function is not currently used
			By noting which other path segment is touched by the circles at each end,
			we can see if anything is to be gained by a further subdivision, since
			if they touch the same bit of path we can move linearly between them.
			Also, we can handle points correctly.
			Parameters:
				end points and indices of limiting path, normal, length
			Returns:
				list of toolpath points
					each a list of 3 reals: x, y coordinates, radius

			"""
			global nlLT, i, j, lmin
			x2=(x0+x1)/2
			y2=(y0+y1)/2
			j2,i2,r2=get_biggest( (x2,y2), (nx,ny))
			if length<lmin : return [ [x2, y2, r2] ]
			if j2==j0 and i2==i0 : #Same as left end. Don't subdivide this part any more
				return [ [x2, y2, r2], line_divide((x2,y2),j2,i2,(x1,y1),j1,i1,(nx,ny),length/2)]
			if j2==j1 and i2==i1 : #Same as right end. Don't subdivide this part any more
				return [ line_divide((x0,y0),j0,i0,(x2,y2),j2,i2,(nx,ny),length/2), [x2, y2, r2] ]
			return [ line_divide((x0,y0),j0,i0,(x2,y2),j2,i2,(nx,ny),length/2), line_divide((x2,y2),j2,i2,(x1,y1),j1,i1,(nx,ny),length/2)]
			#end of line_divide()

		def save_point((x,y),w,i,j,ii,jj):
			"""LT Save this point and delete previous one if linear

			The point is, we generate tons of points but many may be in a straight 3D line.
			There is no benefit in saving the imtermediate points.
			"""
			global wl, cspm
			x=round(x,4) #round to 4 decimals
			y=round(y,4) #round to 4 decimals
			w=round(w,4) #round to 4 decimals
			if len(cspm)>1 :
				xy1a,xy1,xy1b,i1,j1,ii1,jj1=cspm[-1]
				w1=wl[-1]
				if i==i1 and j==j1 and ii==ii1 and jj==jj1 : #one match
					xy1a,xy2,xy1b,i1,j1,ii1,jj1=cspm[-2]
					w2=wl[-2]
					if i==i1 and j==j1 and ii==ii1 and jj==jj1 : #two matches. Now test linearity
						length1=math.hypot(xy1[0]-x,xy1[1]-y)
						length2=math.hypot(xy2[0]-x,xy2[1]-y)
						length12=math.hypot(xy2[0]-xy1[0],xy2[1]-xy1[1])
						#get the xy distance of point 1 from the line 0-2
						if length2>length1 and length2>length12 : #point 1 between them
							xydist=abs( (xy2[0]-x)*(xy1[1]-y)-(xy1[0]-x)*(xy2[1]-y) )/length2
							if xydist<engraving_tolerance : #so far so good
								wdist=w2+(w-w2)*length1/length2 -w1
								if abs(wdist)<engraving_tolerance :
									#print_("pop",j,i,xy1)
									cspm.pop()
									wl.pop()
			cspm+=[ [ [x,y],[x,y],[x,y],i,j,ii,jj ] ]
			wl+=[w]
			#end of save_point

		def draw_point((x0,y0),(x,y),w,t):
			"""LT Draw this point as a circle with a 1px dot in the middle (x,y) 
			and a 3D line from (x0,y0) down to x,y. 3D line thickness should be t/2 

			Note that points that are subsequently erased as being unneeded do get
			displayed, but this helps the user see the total area covered.
			"""
			global gcode_3Dleft ,gcode_3Dright
			if self.options.engraving_draw_calculation_paths :
				inkex.etree.SubElement(	engraving_group, inkex.addNS('path','svg'), 
						{"gcodetools": "Engraving calculation toolpath", 'style':	"fill:#ff00ff; fill-opacity:0.46; stroke:#000000; stroke-width:0.1;", inkex.addNS('cx','sodipodi'):		str(x), inkex.addNS('cy','sodipodi'):		str(y), inkex.addNS('rx','sodipodi'):	str(1), inkex.addNS('ry','sodipodi'): str(1), inkex.addNS('type','sodipodi'):	'arc'})
				#Don't draw zero radius circles
				if w:
					inkex.etree.SubElement(	engraving_group, inkex.addNS('path','svg'), 
						{"gcodetools": "Engraving calculation paths", 'style':	"fill:none; fill-opacity:0.46; stroke:#000000; stroke-width:0.1;", inkex.addNS('cx','sodipodi'):		str(x),  inkex.addNS('cy','sodipodi'):		str(y),inkex.addNS('rx','sodipodi'):		str(w), inkex.addNS('ry','sodipodi'):		str(w), inkex.addNS('type','sodipodi'):	'arc'})
					# Find slope direction for shading
					s=math.atan2(y-y0,x-x0) #-pi to pi
					# convert to 2 hex digits as a shade of red
					s2="#{0:x}0000".format(int(101*(1.5-math.sin(s+0.5))))
					inkex.etree.SubElement(	gcode_3Dleft , inkex.addNS('path','svg'),
					{ "d": "M %f,%f L %f,%f" %(x0-eye_dist,y0,x-eye_dist-0.14*w,y),
						'style': "stroke:" + s2 + "; stroke-opacity:1; stroke-width:" + str(t/2) +" ; fill:none",
						"gcodetools": "Gcode G1R"
					})
					inkex.etree.SubElement(	gcode_3Dright , inkex.addNS('path','svg'),
					{ "d": "M %f,%f L %f,%f" %(x0+eye_dist,y0,x+eye_dist+0.14*r,y),
						'style': "stroke:" + s2 + "; stroke-opacity:1; stroke-width:" + str(t/2) +" ; fill:none",
						"gcodetools": "Gcode G1L"
					})
			#end of draw_point

		#end of subfunction definitions. engraving() starts here:
		gcode = ''
		r,w, wmax = 0,0,0 #theoretical and tool-radius-limited radii in pixels
		x1,y1,nx,ny =0,0,0,0
		cspe =[]
		we = []
		if len(self.selected_paths)<=0:
			self.error(_("Please select at least one path to engrave and run again."),"warning")
			return
		if not self.check_dir() : return
		#Find what units the user uses
		unit=" mm"
		if self.options.unit == "G20 (All units in inches)" :
			unit=" inches"
		elif self.options.unit != "G21 (All units in mm)" :
			self.error(_("Unknown unit selected. mm assumed"),"warning")
		print_("engraving_max_dist mm/inch", self.options.engraving_max_dist )

		#LT See if we can use this parameter for line and Bezier subdivision:
		bitlen=20/self.options.engraving_newton_iterations

		for layer in self.layers :
			if layer in self.selected_paths :
				#Calculate scale in pixels per user unit (mm or inch)
				p1=self.orientation_points[layer][0][0]
				p2=self.orientation_points[layer][0][1]
				ol=math.hypot(p1[0][0]-p2[0][0],p1[0][1]-p2[0][1])
				oluu=math.hypot(p1[1][0]-p2[1][0],p1[1][1]-p2[1][1])
				print_("Orientation2 p1 p2 ol oluu",p1,p2,ol,oluu)
				orientation_scale = ol/oluu

				self.set_tool(layer)
				shape = self.tools[layer][0]['shape']
				if re.search('w', shape) :
					toolshape = eval('lambda w: ' + shape.strip('"'))
				else: 
					self.error(_("Tool '%s' has no shape. 45 degree cone assumed!") % self.tools[layer][0]['name'],"Continue")
					toolshape = lambda w: w
				#Get tool radius in pixels
				toolr=self.tools[layer][0]['diameter'] * orientation_scale/2
				print_("tool radius in pixels=", toolr)
				#max dist from path to engrave in user's units
				max_distuu = min(self.tools[layer][0]['diameter']/2, self.options.engraving_max_dist)
				max_dist=max_distuu*orientation_scale
				print_("max_dist pixels", max_dist )

				engraving_group = inkex.etree.SubElement( self.selected_paths[layer][0].getparent(), inkex.addNS('g','svg') )
				if self.options.engraving_draw_calculation_paths and (self.my3Dlayer  == None) :
					self.my3Dlayer=inkex.etree.SubElement(self.document.getroot(), 'g') #Create a generic element at root level
					self.my3Dlayer.set(inkex.addNS('label', 'inkscape'), "3D") #Gives it a name
					self.my3Dlayer.set(inkex.addNS('groupmode', 'inkscape'), 'layer') #Tells Inkscape it's a layer
				#Create groups for left and right eyes
				if self.options.engraving_draw_calculation_paths :
					gcode_3Dleft = inkex.etree.SubElement(self.my3Dlayer, inkex.addNS('g','svg'), {"gcodetools":"Gcode 3D L"})
					gcode_3Dright = inkex.etree.SubElement(self.my3Dlayer, inkex.addNS('g','svg'), {"gcodetools":"Gcode 3D R"})

				for node in self.selected_paths[layer] :	
					if node.tag == inkex.addNS('path','svg'):
						cspi = cubicsuperpath.parsePath(node.get('d'))
						#LT: Create my own list. n1LT[j] is for subpath j
						nlLT = []
						for j in xrange(len(cspi)): #LT For each subpath...
							# Remove zero length segments, assume closed path
							i = 0 #LT was from i=1
							while i<len(cspi[j]):
								if abs(cspi[j][i-1][1][0]-cspi[j][i][1][0])<engraving_tolerance and abs(cspi[j][i-1][1][1]-cspi[j][i][1][1])<engraving_tolerance:
									cspi[j][i-1][2] = cspi[j][i][2]
									del cspi[j][i]
								else:
									i += 1
						for csp in cspi: #LT6a For each subpath...
							#Create copies in 3D layer
							print_("csp is zz ",csp)
							cspl=[]
							cspr=[]
							#create list containing lines and points, starting with a point
							# line members: [x,y],[nx,ny],False,i
							# x,y is start of line. Normal on engraved side.
							# Normal is normalised (unit length)
							#Note that Y axis increases down the page
							# corner members: [x,y],[nx,ny],True,sin(halfangle)
							# if halfangle>0: radius 0 here. normal is bisector
							# if halfangle<0. reflex angle. normal is bisector
							# corner normals are divided by cos(halfangle)
							#so that they will engrave correctly
							print_("csp is",csp)
							nlLT.append ([])
							for i in range(0,len(csp)): #LT for each point
								#n = []
								sp0, sp1, sp2 = csp[i-2], csp[i-1], csp[i]
								if self.options.engraving_draw_calculation_paths:
									#Copy it to 3D layer objects
									spl=[]
									spr=[]
									for j in range(0,3) :
										pl=[sp2[j][0]-eye_dist,sp2[j][1]]
										pr=[sp2[j][0]+eye_dist,sp2[j][1]]
										spl+=[pl]
										spr+=[pr]
									cspl+=[spl]
									cspr+=[spr]					
								#LT find angle between this and previous segment
								x0,y0 = sp1[1]
								nx1,ny1 = csp_normalized_normal(sp1,sp2,0)
								#I don't trust this function, so test result
								if abs(1-math.hypot(nx1,ny1))> 0.00001 :
									print_("csp_normalised_normal error t=0",nx1,ny1,sp1,sp2)
									self.error(_("csp_normalised_normal error. See log."),"warning")

								nx0, ny0 = csp_normalized_normal(sp0,sp1,1)
								if abs(1-math.hypot(nx0,ny0))> 0.00001 :
									print_("csp_normalised_normal error t=1",nx0,ny0,sp1,sp2)
									self.error(_("csp_normalised_normal error. See log."),"warning")
								bx,by,s=bisect((nx0,ny0),(nx1,ny1))
								#record x,y,normal,ifCorner, sin(angle-turned/2)
								nlLT[-1] += [[ [x0,y0],[bx,by], True, s]]

								#LT now do the line
								if sp1[1]==sp1[2] and sp2[0]==sp2[1] : #straightline
									nlLT[-1]+=[[sp1[1],[nx1,ny1],False,i]]
								else : #Bezier. First, recursively cut it up:
									nn=bez_divide(sp1[1],sp1[2],sp2[0],sp2[1])
									first=True #Flag entry to divided Bezier
									for bLT in nn : #save as two line segments
										for seg in range(3) :
											if seg>0 or first :
												nx1=bLT[seg][1]-bLT[seg+1][1]
												ny1=bLT[seg+1][0]-bLT[seg][0]
												l1=math.hypot(nx1,ny1)
												if l1<engraving_tolerance :
													continue
												nx1=nx1/l1 #normalise them
												ny1=ny1/l1
												nlLT[-1]+=[[bLT[seg],[nx1,ny1], False,i]]
												first=False
											if seg<2 : #get outgoing bisector
												nx0=nx1
												ny0=ny1
												nx1=bLT[seg+1][1]-bLT[seg+2][1]
												ny1=bLT[seg+2][0]-bLT[seg+1][0]
												l1=math.hypot(nx1,ny1)
												if l1<engraving_tolerance :
													continue
												nx1=nx1/l1 #normalise them
												ny1=ny1/l1
												#bisect
												bx,by,s=bisect((nx0,ny0),(nx1,ny1))
												nlLT[-1] += [[bLT[seg+1],[bx,by], True, 0.]]
							#LT for each segment - ends here.
							print_(("engraving_draw_calculation_paths=",self.options.engraving_draw_calculation_paths))
							if self.options.engraving_draw_calculation_paths:
								#Copy complete paths to 3D layer
								#print_("cspl",cspl)
								cspl+=[cspl[0]] #Close paths
								cspr+=[cspr[0]] #Close paths
								inkex.etree.SubElement(	gcode_3Dleft , inkex.addNS('path','svg'),
								{ "d": cubicsuperpath.formatPath([cspl]),
								'style': "stroke:#808080; stroke-opacity:1; stroke-width:0.6; fill:none",
								"gcodetools": "G1L outline"
								})
								inkex.etree.SubElement(	gcode_3Dright , inkex.addNS('path','svg'),
								{ "d": cubicsuperpath.formatPath([cspr]),
								'style': "stroke:#808080; stroke-opacity:1; stroke-width:0.6; fill:none",
								"gcodetools": "G1L outline"
								})

								for p in nlLT[-1]: #For last sub-path
									if p[2]: inkex.etree.SubElement(	engraving_group, inkex.addNS('path','svg'),
										{ "d":	"M %f,%f L %f,%f" %(p[0][0],p[0][1],p[0][0]+p[1][0]*10,p[0][1]+p[1][1]*10),
											'style':	"stroke:#f000af; stroke-opacity:0.46; stroke-width:0.1; fill:none",
											"gcodetools": "Engraving normals"
										})				
									else: inkex.etree.SubElement(	engraving_group, inkex.addNS('path','svg'),
										{ "d":	"M %f,%f L %f,%f" %(p[0][0],p[0][1],p[0][0]+p[1][0]*10,p[0][1]+p[1][1]*10),
											'style':	"stroke:#0000ff; stroke-opacity:0.46; stroke-width:0.1; fill:none",
											"gcodetools": "Engraving bisectors"
										})				


						#LT6a build nlLT[j] for each subpath - ends here
						#for nnn in nlLT :
							#print_("nlLT",nnn) #LT debug stuff
				 		# Calculate offset points
						reflex=False
						for j in xrange(len(nlLT)): #LT6b for each subpath
							cspm=[] #Will be my output. List of csps.
							wl=[] #Will be my w output list
							w = r = 0 #LT initial, as first point is an angle
							for i in xrange(len(nlLT[j])) : #LT for each node
								#LT Note: Python enables wrapping of array indices
								# backwards to -1, -2, but not forwards. Hence:
								n0 = nlLT[j][i-2] #previous node
								n1 = nlLT[j][i-1] #current node
								n2 = nlLT[j][i] #next node
								#if n1[2] == True and n1[3]==0 : # A straight angle
									#continue
								x1a,y1a = n1[0] #this point/start of this line
								nx,ny = n1[1]
								x1b,y1b = n2[0] #next point/end of this line
								if n1[2] == True : # We're at a corner
									bits=1
									bit0=0
									#lastr=r #Remember r from last line
									lastw=w #Remember w from last line
									w = max_dist
									if n1[3]>0 : #acute. Limit radius
										len1=math.hypot( (n0[0][0]-n1[0][0]),( n0[0][1]-n1[0][1]) )
										if i<(len(nlLT[j])-1) :
											len2=math.hypot( (nlLT[j][i+1][0][0]-n1[0][0]),(nlLT[j][i+1][0][1]-n1[0][1]) )
										else:
											len2=math.hypot( (nlLT[j][0][0][0]-n1[0][0]),(nlLT[j][0][0][1]-n1[0][1]) )
										#set initial r value, not to be exceeded
										w = math.sqrt(min(len1,len2))/n1[3]
								else: #line. Cut it up if long.
									if n0[3]>0 and not self.options.engraving_draw_calculation_paths :
										bit0=r*n0[3] #after acute corner
									else : bit0=0.0
									length=math.hypot((x1b-x1a),(y1a-y1b))
									bit0=(min(length,bit0))
									bits=int((length-bit0)/bitlen)
									#split excess evenly at both ends
									bit0+=(length-bit0-bitlen*bits)/2
									#print_("j,i,r,bit0,bits",j,i,w,bit0,bits)
								for b in xrange(bits) : #divide line into bits
									x1=x1a+ny*(b*bitlen+bit0)
									y1=y1a-nx*(b*bitlen+bit0)
									jjmin,iimin,w=get_biggest( (x1,y1), (nx,ny))
									print_("i,j,jjmin,iimin,w",i,j,jjmin,iimin,w)
									#w = min(r, toolr)
									wmax=max(wmax,w)
									if reflex : #just after a reflex corner
										reflex = False
										if w<lastw : #need to adjust it
											draw_point((x1,y1),(n0[0][0]+n0[1][0]*w,n0[0][1]+n0[1][1]*w),w, (lastw-w)/2)
											save_point((n0[0][0]+n0[1][0]*w,n0[0][1]+n0[1][1]*w),w,i,j,iimin,jjmin)
									if n1[2] == True : # We're at a corner
										if n1[3]>0 : #acute
											save_point((x1+nx*w,y1+ny*w),w,i,j,iimin,jjmin)
											draw_point((x1,y1),(x1,y1),0,0)
											save_point((x1,y1),0,i,j,iimin,jjmin)
										elif n1[3]<0  : #reflex
											if w>lastw :
												draw_point((x1,y1),(x1+nx*lastw,y1+ny*lastw),w, (w-lastw)/2)
												wmax=max(wmax,w)
												save_point((x1+nx*w,y1+ny*w),w,i,j,iimin,jjmin)
									elif b>0 and n2[3]>0 and not self.options.engraving_draw_calculation_paths : #acute corner coming up
										if jjmin==j and iimin==i+2 : break
									draw_point((x1,y1),(x1+nx*w,y1+ny*w),w, bitlen)
									save_point((x1+nx*w,y1+ny*w),w,i,j,iimin,jjmin)

								#LT end of for each bit of this line
								if n1[2] == True and n1[3]<0 : #reflex angle
									reflex=True
								lastw = w #remember this w
							#LT next i
							cspm+=[cspm[0]]
							print_("cspm",cspm)
							wl+=[wl[0]]
							print_("wl",wl)
							#Note: Original csp_points was a list, each element
							#being 4 points, with the first being the same as the
							#last of the previous set.
							#Each point is a list of [cx,cy,r,w]
							#I have flattened it to a flat list of points.
					
							if self.options.engraving_draw_calculation_paths==True:
								node =  inkex.etree.SubElement(	engraving_group, inkex.addNS('path','svg'), 										{
														 "d":	 cubicsuperpath.formatPath([cspm]),
														'style':	styles["biarc_style_i"]['biarc1'],
														"gcodetools": "Engraving calculation paths",
													})
								for i in xrange(len(cspm)):
									inkex.etree.SubElement(	engraving_group, inkex.addNS('path','svg'), 
											{"gcodetools": "Engraving calculation paths", 'style':	"fill:none; fill-opacity:0.46; stroke:#000000; stroke-width:0.1;", inkex.addNS('cx','sodipodi'):		str(cspm[i][1][0]),  inkex.addNS('cy','sodipodi'):		str(cspm[i][1][1]),inkex.addNS('rx','sodipodi'):		str(wl[i]), inkex.addNS('ry','sodipodi'):		str(wl[i]), inkex.addNS('type','sodipodi'):	'arc'})
							cspe += [cspm]
							wluu = [] #width list in user units: mm/inches
							for w in wl :
								wluu+=[ w / orientation_scale ]
							print_("wl in pixels",wl)
							print_("wl in user units",wluu)
							#LT previously, we was in pixels so gave wrong depth
							we   +=	[wluu]
						#LT6b For each subpath - ends here			
					#LT5 if it is a path - ends here
					#print_("cspe",cspe)
					#print_("we",we)
				#LT4 for each selected object in this layer - ends here

				if cspe!=[]:
					curve = self.parse_curve(cspe, layer, we, toolshape) #convert to lines
					self.draw_curve(curve, layer, engraving_group)
					gcode += self.generate_gcode(curve, layer, self.options.Zsurface)

			#LT3 for layers loop ends here
		if gcode!='' :
			self.header+="(Tool diameter should be at least "+str(2*wmax/orientation_scale)+unit+ ")\n"
			self.header+="(Depth, as a function of radius w, must be "+ self.tools[layer][0]['shape']+ ")\n"
			self.header+="(Rapid feeds use safe Z="+ str(self.options.Zsafe) + unit + ")\n"
			self.header+="(Material surface at Z="+ str(self.options.Zsurface) + unit + ")\n"
			self.export_gcode(gcode,comments=self.tools[layer][0]["comments"])
		else : 	self.error(_("No need to engrave sharp angles."),"warning")


################################################################################
###
###		Orientation
###
################################################################################
	def orientation(self, layer=None) :

		if layer == None :
			layer = self.current_layer if self.current_layer is not None else self.document.getroot()
		
		transform = self.get_transforms(layer)
		if transform != [] : 
			transform = self.reverse_transform(transform)
			transform = simpletransform.formatTransform(transform)

		if self.options.orientation_points_count == "graffiti" :
			print_(self.graffiti_reference_points)
			print_("Inserting graffiti points")
			if layer in self.graffiti_reference_points: graffiti_reference_points_count =  len(self.graffiti_reference_points[layer])
			else: graffiti_reference_points_count = 0
			axis = ["X","Y","Z","A"][graffiti_reference_points_count%4]
			attr = {'gcodetools': "Gcodetools graffiti reference point"}
			if 	transform != [] :
				attr["transform"] = transform 
			g = inkex.etree.SubElement(layer, inkex.addNS('g','svg'), attr)
			inkex.etree.SubElement(	g, inkex.addNS('path','svg'), 
				{
					'style':	"stroke:none;fill:#00ff00;", 	
					'd':'m %s,%s 2.9375,-6.343750000001 0.8125,1.90625 6.843748640396,-6.84374864039 0,0 0.6875,0.6875 -6.84375,6.84375 1.90625,0.812500000001 z z' % (graffiti_reference_points_count*100, 0),
					'gcodetools': "Gcodetools graffiti reference point arrow"
				})
			
			draw_text(axis,graffiti_reference_points_count*100+10,-10, group = g, gcodetools_tag = "Gcodetools graffiti reference point text")

		elif self.options.orientation_points_count == "in-out reference point" :
			draw_pointer(group = self.current_layer, x = self.view_center, figure="arrow", pointer_type = "In-out reference point", text = "In-out point")
	
		else :
			print_("Inserting orientation points")

			if layer in self.orientation_points:
				self.error(_("Active layer already has orientation points! Remove them or select another layer!"),"active_layer_already_has_orientation_points")
			
			attr = {"gcodetools":"Gcodetools orientation group"}
			if 	transform != [] :
				attr["transform"] = transform 

			orientation_group = inkex.etree.SubElement(layer, inkex.addNS('g','svg'), attr)
			doc_height = inkex.unittouu(self.document.getroot().get('height'))
			if self.document.getroot().get('height') == "100%" :
				doc_height = 1052.3622047
				print_("Overruding height from 100 percents to %s" % doc_height)
			if self.options.unit == "G21 (All units in mm)" : 
				points = [[0.,0.,self.options.Zsurface],[100.,0.,self.options.Zdepth],[0.,100.,0.]]
				orientation_scale = 3.5433070660
				print_("orientation_scale < 0 ===> switching to mm units=%0.10f"%orientation_scale )
			elif self.options.unit == "G20 (All units in inches)" :
				points = [[0.,0.,self.options.Zsurface],[5.,0.,self.options.Zdepth],[0.,5.,0.]]
				orientation_scale = 90
				print_("orientation_scale < 0 ===> switching to inches units=%0.10f"%orientation_scale )
			if self.options.orientation_points_count == "2" :
				points = points[:2]
			print_(("using orientation scale",orientation_scale,"i=",points))
			for i in points :
				si = [i[0]*orientation_scale, i[1]*orientation_scale]
				g = inkex.etree.SubElement(orientation_group, inkex.addNS('g','svg'), {'gcodetools': "Gcodetools orientation point (%s points)" % self.options.orientation_points_count})
				inkex.etree.SubElement(	g, inkex.addNS('path','svg'), 
					{
						'style':	"stroke:none;fill:#000000;", 	
						'd':'m %s,%s 2.9375,-6.343750000001 0.8125,1.90625 6.843748640396,-6.84374864039 0,0 0.6875,0.6875 -6.84375,6.84375 1.90625,0.812500000001 z z' % (si[0], -si[1]+doc_height),
						'gcodetools': "Gcodetools orientation point arrow"
					})

				draw_text("(%s; %s; %s)" % (i[0],i[1],i[2]), (si[0]+10), (-si[1]-10+doc_height), group = g, gcodetools_tag = "Gcodetools orientation point text")

		
################################################################################
###
###		Tools library
###
################################################################################
	def tools_library(self, layer=None) :
		# Add a tool to the drawing
		if layer == None :
			layer = self.current_layer if self.current_layer is not None else self.document.getroot()
		if layer in self.tools:
			self.error(_("Active layer already has a tool! Remove it or select another layer!"),"active_layer_already_has_tool")

		if self.options.tools_library_type == "cylinder cutter" :
			tool = {
					"name": "Cylindrical cutter",
					"id": "Cylindrical cutter 0001",
					"diameter":10,
					"penetration angle":90,
					"feed":"400",
					"penetration feed":"100",
					"depth step":"1",
					"tool change gcode":" ",
					"comments":" "
			}
		elif self.options.tools_library_type == "plotter" :
			tool = {
					"name": "Plotter",
					"id": "Plotter 0001",
					"diameter":0.4,
					"feed":"1000",
					"penetration feed":"1500",
					"depth step":"1",
					"tool change gcode":" ",
					"comments":" "
			}
		elif self.options.tools_library_type == "lathe cutter" :
			tool = {
					"name": "Lathe cutter",
					"id": "Lathe cutter 0001",
					"diameter":10,
					"penetration angle":90,
					"feed":"400",
					"passing feed":"800",
					"fine feed":"100",
					"penetration feed":"100",
					"depth step":"1",
					"tool change gcode":" ",
					"comments":" "
			}
		elif self.options.tools_library_type == "cone cutter":	
			tool = {
					"name": "Cone cutter",
					"id": "Cone cutter 0001",
					"diameter":10,
					"shape":"w",
					"feed":"400",
					"penetration feed":"100",
					"depth step":"1",
					"tool change gcode":" ",
					"comments":" "
			}
		elif self.options.tools_library_type == "tangent knife":	
			tool = {
					"name": "Tangent knife",
					"id": "Tangent knife 0001",
					"feed":"400",
					"penetration feed":"100",
					"depth step":"100",
					"4th axis meaning": "tangent knife",
					"4th axis scale": 1.,
					"4th axis offset": 0,
					"tool change gcode":" ",
					"comments":" "
			}
			
		elif self.options.tools_library_type == "plasma cutter":	
			tool = {
				"name": "Plasma cutter",
				"id": "Plasma cutter 0001",
				"diameter":10,
				"penetration feed":100,
				"feed":400,
				"gcode before path":"""G31 Z-100 F500 (find metal)
G92 Z0 (zero z)
G00 Z10 F500 (going up)
M03 (turn on plasma)
G04 P0.2 (pause)
G01 Z1 (going to cutting z)\n""",
				"gcode after path":"M05 (turn off plasma)\n",
				"comments":" "
			}
		elif self.options.tools_library_type == "graffiti":	
			tool = {
				"name": "Graffiti",
				"id": "Graffiti 0001",
				"diameter":10,
				"penetration feed":100,
				"feed":400,
				"gcode before path":"""M03 S1(Turn spray on)\n """,
				"gcode after path":"M05 (Turn spray off)\n ",
				"tool change gcode":"(Add G00 here to change sprayer if needed)\n",
				"comments":" "
			}

		else :
			tool = self.default_tool
		
		tool_num = sum([len(self.tools[i]) for i in self.tools])
		colors = ["00ff00","0000ff","ff0000","fefe00","00fefe", "fe00fe", "fe7e00", "7efe00", "00fe7e", "007efe", "7e00fe", "fe007e"]
		
		tools_group = inkex.etree.SubElement(layer, inkex.addNS('g','svg'), {'gcodetools': "Gcodetools tool definition"})
		bg = inkex.etree.SubElement(	tools_group, inkex.addNS('path','svg'), 
					{'style':	"fill:#%s;fill-opacity:0.5;stroke:#444444; stroke-width:1px;"%colors[tool_num%len(colors)], "gcodetools":"Gcodetools tool background"})

		y = 0
		keys = []
		for key in self.tools_field_order:
			if key in tool: keys += [key]
		for key in tool:
			if key not in keys: keys += [key]
		for key in keys :
			g = inkex.etree.SubElement(tools_group, inkex.addNS('g','svg'), {'gcodetools': "Gcodetools tool parameter"})
			draw_text(key, 0, y, group = g, gcodetools_tag = "Gcodetools tool definition field name", font_size = 10 if key!='name' else 20)
			param = tool[key]
			if type(param)==str and re.match("^\s*$",param) : param = "(None)"
			draw_text(param, 150, y, group = g, gcodetools_tag = "Gcodetools tool definition field value", font_size = 10 if key!='name' else 20)
			v = str(param).split("\n")
			y += 15*len(v) if key!='name' else 20*len(v)

		bg.set('d',"m -20,-20 l 400,0 0,%f -400,0 z " % (y+50))
		tool = []
		tools_group.set("transform", simpletransform.formatTransform([ [1,0,self.view_center[0]-150 ], [0,1,self.view_center[1]] ] ))


################################################################################
###
###		Check tools and OP asignment
###
################################################################################
	def check_tools_and_op(self):
		if len(self.selected)<=0 :
			self.error(_("Selection is empty! Will compute whole drawing."),"selection_is_empty_will_comupe_drawing")
			paths = self.paths
		else :
			paths = self.selected_paths
		#	Set group
		group = inkex.etree.SubElement( self.selected_paths.keys()[0] if len(self.selected_paths.keys())>0 else self.layers[0], inkex.addNS('g','svg') )
		trans_ = [[1,0.3,0],[0,0.5,0]]	

		self.set_markers()

		bounds = [float('inf'),float('inf'),float('-inf'),float('-inf')]
		tools_bounds = {}
		for layer in self.layers :
			if layer in paths :
				self.set_tool(layer)
				tool = self.tools[layer][0]
				tools_bounds[layer] = tools_bounds[layer] if layer in tools_bounds else [float("inf"),float("-inf")]
				style = simplestyle.formatStyle(tool["style"])
				for path in paths[layer] :
					style = "fill:%s; fill-opacity:%s; stroke:#000044; stroke-width:1; marker-mid:url(#CheckToolsAndOPMarker);" % (
					tool["style"]["fill"] if "fill" in tool["style"] else "#00ff00", 
					tool["style"]["fill-opacity"] if "fill-opacity" in tool["style"] else "0.5")
					group.insert( 0, inkex.etree.Element(path.tag, path.attrib))
					new = group.getchildren()[0]
					new.set("style", style)
					
					trans = self.get_transforms(path)
					trans = simpletransform.composeTransform( trans_, trans if trans != [] else [[1.,0.,0.],[0.,1.,0.]])
					csp = cubicsuperpath.parsePath(path.get("d"))
					simpletransform.applyTransformToPath(trans,csp)
					path_bounds = csp_simple_bound(csp)
					trans = simpletransform.formatTransform(trans)
					bounds = [min(bounds[0],path_bounds[0]), min(bounds[1],path_bounds[1]), max(bounds[2],path_bounds[2]), max(bounds[3],path_bounds[3])]
					tools_bounds[layer] = [min(tools_bounds[layer][0], path_bounds[1]), max(tools_bounds[layer][1], path_bounds[3])] 

					new.set("transform", trans) 
					trans_[1][2] += 20
				trans_[1][2] += 100

		for layer in self.layers :
			if layer in self.tools :
				if layer in tools_bounds :
					tool = self.tools[layer][0]
					g = copy.deepcopy(tool["self_group"])
					g.attrib["gcodetools"] = "Check tools and OP asignment"
					trans = [[1,0.3,bounds[2]],[0,0.5,tools_bounds[layer][0]]]	
					g.set("transform",simpletransform.formatTransform(trans))
					group.insert( 0, g )


################################################################################
###		TODO Launch browser on help tab
################################################################################
	def help(self):
		self.error(_("""Tutorials, manuals and support can be found at\nEnglish support forum:\n	http://www.cnc-club.ru/gcodetools\nand Russian support forum:\n	http://www.cnc-club.ru/gcodetoolsru"""),"warning")
		return


################################################################################
###		Lathe
################################################################################
	def generate_lathe_gcode(self, subpath, layer, feed_type) :
		if len(subpath) <2 : return ""
		feed = " F %f" % self.tool[feed_type] 
		x,z = self.options.lathe_x_axis_remap, self.options.lathe_z_axis_remap
		flip_angle = -1 if x.lower()+z.lower() in ["xz", "yx", "zy"] else 1
		alias = {"X":"I", "Y":"J", "Z":"K", "x":"i", "y":"j", "z":"k"} 
		i_, k_ = alias[x], alias[z]
		c = [ [subpath[0][1], "move", 0, 0, 0] ]
		#draw_csp(self.transform_csp([subpath],layer,True), color = "Orange", width = .1)
		for sp1,sp2 in zip(subpath,subpath[1:]) :
			c += biarc(sp1,sp2,0,0)
		for i in range(1,len(c)) : # Just in case check end point of each segment
			c[i-1][4] = c[i][0][:]
		c += [ [subpath[-1][1], "end", 0, 0, 0] ]			
		self.draw_curve(c, layer, style = styles["biarc_style_lathe_%s" % feed_type])
		
		gcode = ("G01 %s %f %s %f" % (x, c[0][4][0], z, c[0][4][1]) ) + feed + "\n" # Just in case move to the start...
		for s in c :
			if s[1] == 'line':
				gcode += ("G01 %s %f %s %f" % (x, s[4][0], z, s[4][1]) ) + feed + "\n"
			elif s[1] == 'arc':
				r = [(s[2][0]-s[0][0]), (s[2][1]-s[0][1])]
				if (r[0]**2 + r[1]**2)>self.options.min_arc_radius**2:
					r1, r2 = (P(s[0])-P(s[2])), (P(s[4])-P(s[2]))
					if abs(r1.mag()-r2.mag()) < 0.001 :
						gcode += ("G02" if s[3]*flip_angle<0 else "G03") + (" %s %f %s %f %s %f %s %f" % (x,s[4][0],z,s[4][1],i_,(s[2][0]-s[0][0]), k_, (s[2][1]-s[0][1]) ) ) + feed + "\n"
					else:
						r = (r1.mag()+r2.mag())/2
						gcode += ("G02" if s[3]*flip_angle<0 else "G03") + (" %s %f %s %f" % (x,s[4][0],z,y[4][1]) ) + " R%f"%r + feed + "\n"
		return gcode


	def lathe(self):
		if not self.check_dir() : return
		x,z = self.options.lathe_x_axis_remap, self.options.lathe_z_axis_remap
		x = re.sub("^\s*([XYZxyz])\s*$",r"\1",x) 
		z = re.sub("^\s*([XYZxyz])\s*$",r"\1",z)
		if x not in ["X", "Y", "Z", "x", "y", "z"] or z not in ["X", "Y", "Z", "x", "y", "z"] :
			self.error(_("Lathe X and Z axis remap should be 'X', 'Y' or 'Z'. Exiting..."),"warning") 
			return
		if x.lower() == z.lower() :
			self.error(_("Lathe X and Z axis remap should be the same. Exiting..."),"warning") 
			return
		if 	x.lower()+z.lower() in ["xy","yx"] : gcode_plane_selection = "G17 (Using XY plane)\n"
		if 	x.lower()+z.lower() in ["xz","zx"] : gcode_plane_selection = "G18 (Using XZ plane)\n"
		if 	x.lower()+z.lower() in ["zy","yz"] : gcode_plane_selection = "G19 (Using YZ plane)\n"
		self.options.lathe_x_axis_remap, self.options.lathe_z_axis_remap = x, z
	
		paths = self.selected_paths
		self.tool = []
		gcode = ""
		for layer in self.layers :
			if layer in paths :
				self.set_tool(layer)
				if self.tool != self.tools[layer][0] :
					self.tool = self.tools[layer][0]
					self.tool["passing feed"]	= float(self.tool["passing feed"] if "passing feed" in self.tool else self.tool["feed"])
					self.tool["feed"]			= float(self.tool["feed"])
					self.tool["fine feed"]		= float(self.tool["fine feed"] if "fine feed" in self.tool else self.tool["feed"]) 
					gcode += ( "(Change tool to %s)\n" % re.sub("\"'\(\)\\\\"," ",self.tool["name"]) ) + self.tool["tool change gcode"] + "\n"
					
				for path in paths[layer]:
					csp = self.transform_csp(cubicsuperpath.parsePath(path.get("d")),layer)
					
					for subpath in csp :
						# Offset the path if fine cut is defined.
						fine_cut = subpath[:]
						if self.options.lathe_fine_cut_width>0 :
							r = self.options.lathe_fine_cut_width
							if self.options.lathe_create_fine_cut_using == "Move path" :
								subpath = [ [  [i2[0],i2[1]+r]  for i2 in i1]  for i1 in subpath]
							else :
								# Close the path to make offset correct 
								bound = csp_simple_bound([subpath])
								minx,miny,maxx,maxy = csp_true_bounds([subpath])
								offsetted_subpath = csp_subpath_line_to(subpath[:], [ [subpath[-1][1][0], miny[1]-r*10 ], [subpath[0][1][0], miny[1]-r*10 ], [subpath[0][1][0], subpath[0][1][1] ]  ])
								left,right = subpath[-1][1][0], subpath[0][1][0]
								if left>right : left, right = right,left
								offsetted_subpath = csp_offset([offsetted_subpath], r if not csp_subpath_ccw(offsetted_subpath) else -r ) 
								offsetted_subpath = csp_clip_by_line(offsetted_subpath,  [left,10], [left,0] )
								offsetted_subpath = csp_clip_by_line(offsetted_subpath,  [right,0], [right,10] )
								offsetted_subpath = csp_clip_by_line(offsetted_subpath,  [0, miny[1]-r], [10, miny[1]-r] )
								#draw_csp(self.transform_csp(offsetted_subpath,layer,True), color = "Green", width = 1)
								# Join offsetted_subpath together 
								# Hope there wont be any cicles
								subpath = csp_join_subpaths(offsetted_subpath)[0]
						
						# Create solid object from path and lathe_width 
						bound = csp_simple_bound([subpath])
						top_start, top_end = [subpath[0][1][0], self.options.lathe_width+self.options.Zsafe+self.options.lathe_fine_cut_width], [subpath[-1][1][0], self.options.lathe_width+self.options.Zsafe+self.options.lathe_fine_cut_width]

						gcode += ("G01 %s %f F %f \n" % (z, top_start[1], self.tool["passing feed"]) )
						gcode += ("G01 %s %f %s %f F %f \n" % (x, top_start[0], z, top_start[1], self.tool["passing feed"]) )

						subpath = csp_concat_subpaths(csp_subpath_line_to([],[top_start,subpath[0][1]]), subpath)
						subpath = csp_subpath_line_to(subpath,[top_end,top_start])
	
						
						width = max(0, self.options.lathe_width - max(0, bound[1]) )
						step = self.tool['depth step']
						steps = int(math.ceil(width/step))
						for i in range(steps+1):
							current_width = self.options.lathe_width - step*i
							intersections = []
							for j in range(1,len(subpath)) :
								sp1,sp2 = subpath[j-1], subpath[j]
								intersections += [[j,k] for k in csp_line_intersection([bound[0]-10,current_width], [bound[2]+10,current_width], sp1, sp2)]
								intersections += [[j,k] for k in csp_line_intersection([bound[0]-10,current_width+step], [bound[2]+10,current_width+step], sp1, sp2)]
							parts = csp_subpath_split_by_points(subpath,intersections)
							for part in parts :
								minx,miny,maxx,maxy = csp_true_bounds([part])
								y = (maxy[1]+miny[1])/2
								if  y > current_width+step :
									gcode += self.generate_lathe_gcode(part,layer,"passing feed")
								elif current_width <= y <= current_width+step :
									gcode += self.generate_lathe_gcode(part,layer,"feed")
								else :
									# full step cut
									part = csp_subpath_line_to([], [part[0][1], part[-1][1]] )
									gcode += self.generate_lathe_gcode(part,layer,"feed")
									
						top_start, top_end = [fine_cut[0][1][0], self.options.lathe_width+self.options.Zsafe+self.options.lathe_fine_cut_width], [fine_cut[-1][1][0], self.options.lathe_width+self.options.Zsafe+self.options.lathe_fine_cut_width]
						gcode += "\n(Fine cutting start)\n(Calculating fine cut using %s)\n"%self.options.lathe_create_fine_cut_using
						for i in range(self.options.lathe_fine_cut_count) :
							width = self.options.lathe_fine_cut_width*(1-float(i+1)/self.options.lathe_fine_cut_count ) 
							if width == 0 : 
								current_pass = fine_cut							
							else :	
								if self.options.lathe_create_fine_cut_using == "Move path" :
									current_pass = [ [  [i2[0],i2[1]+width]  for i2 in i1]  for i1 in fine_cut]
								else :
									minx,miny,maxx,maxy = csp_true_bounds([fine_cut])
									offsetted_subpath = csp_subpath_line_to(fine_cut[:], [ [fine_cut[-1][1][0], miny[1]-r*10 ], [fine_cut[0][1][0], miny[1]-r*10 ], [fine_cut[0][1][0], fine_cut[0][1][1] ]  ])
									left,right = fine_cut[-1][1][0], fine_cut[0][1][0]
									if left>right : left, right = right,left
									offsetted_subpath = csp_offset([offsetted_subpath], width if not csp_subpath_ccw(offsetted_subpath) else -width ) 
									offsetted_subpath = csp_clip_by_line(offsetted_subpath,  [left,10], [left,0] )
									offsetted_subpath = csp_clip_by_line(offsetted_subpath,  [right,0], [right,10] )
									offsetted_subpath = csp_clip_by_line(offsetted_subpath,  [0, miny[1]-r], [10, miny[1]-r] )
									current_pass = csp_join_subpaths(offsetted_subpath)[0]


							gcode += "\n(Fine cut %i-th cicle start)\n"%(i+1)					
							gcode += ("G01 %s %f %s %f F %f \n" % (x, top_start[0], z, top_start[1], self.tool["passing feed"]) )
							gcode += ("G01 %s %f %s %f F %f \n" % (x, current_pass[0][1][0], z, current_pass[0][1][1]+self.options.lathe_fine_cut_width, self.tool["passing feed"]) )
							gcode += ("G01 %s %f %s %f F %f \n" % (x, current_pass[0][1][0], z, current_pass[0][1][1], self.tool["fine feed"]) )
						
							gcode += self.generate_lathe_gcode(current_pass,layer,"fine feed")
							gcode += ("G01 %s %f F %f \n" % (z, top_start[1], self.tool["passing feed"]) )
							gcode += ("G01 %s %f %s %f F %f \n" % (x, top_start[0], z, top_start[1], self.tool["passing feed"]) )
	
		self.export_gcode(gcode,comments=self.tools[layer][0]["comments"])
		
################################################################################
###
###		Lathe modify path 
### 	Modifies path to fit current cutter. As for now straight rect cutter.
###
################################################################################

	def lathe_modify_path(self):
		if self.selected_paths == {} and self.options.auto_select_paths:
			paths=self.paths
			self.error(_("No paths are selected! Trying to work on all available paths."),"warning")
		else :
			paths = self.selected_paths

		for layer in self.layers :
			if layer in paths :
				width = self.options.lathe_rectangular_cutter_width
				#self.set_tool(layer)
				for path in paths[layer]:
					csp = self.transform_csp(cubicsuperpath.parsePath(path.get("d")),layer)
					new_csp = []
					for subpath in csp: 
						orientation = subpath[-1][1][0]>subpath[0][1][0]
						last_n = None
						last_o = 0
						new_subpath = []

						# Split segment at x' and y' == 0
						for sp1, sp2 in zip(subpath[:],subpath[1:]):
							ax,ay,bx,by,cx,cy,dx,dy = csp_parameterize(sp1,sp2)
							roots = cubic_solver_real(0, 3*ax, 2*bx, cx)
							roots += cubic_solver_real(0, 3*ay, 2*by, cy)
							new_subpath = csp_concat_subpaths(new_subpath, csp_seg_split(sp1,sp2,roots))
						subpath = new_subpath
						new_subpath = []
						first_seg = True
						for sp1, sp2 in zip(subpath[:],subpath[1:]):
							n = csp_normalized_normal(sp1,sp2,0)
							a  = math.atan2(n[0],n[1])
							if a == 0 or a == math.pi :
								n = csp_normalized_normal(sp1,sp2,1)
							a  = math.atan2(n[0],n[1])							
							if a!=0 and a!=math.pi:
								o = 0 if 0<a<=math.pi/2 or -math.pi<a<-math.pi/2 else 1
								if not orientation: o = 1-o
								
								# Add first horisontal straight line if needed
								if not first_seg and new_subpath==[] : new_subpath = [ [[subpath[0][i][0] - width*o ,subpath[0][i][1]] for i in range(3)] ]
								
								new_subpath = csp_concat_subpaths(
										new_subpath,
										[
											[[sp1[i][0] - width*o ,sp1[i][1]] for i in range(3)],
											[[sp2[i][0] - width*o ,sp2[i][1]] for i in range(3)]
										]
									)
							first_seg = False
							
						# Add last horisontal straigth line if needed
						if a==0 or a==math.pi :
							new_subpath +=  [ [[subpath[-1][i][0] - width*o ,subpath[-1][i][1]] for i in range(3)] ]

						
					new_csp += [new_subpath]	
					self.draw_csp(new_csp,layer)
#								
#								o = (1 if cross(n, [0,1])>0 else -1)*orientation
#								new_subpath += [  [sp1[i][0] - width*o,sp1[i][1]] for i in range(3)  ]
#							n = csp_normalized_normal(sp1,sp2,1) 
#							o = (1 if cross(n, [0,1])>0 else -1)*orientation
#							new_subpath += [  [sp2[i][0] - width*o,sp2[i][1]] for i in range(3)  ]
							
							
################################################################################
###
### Update function
###
###	Gets file containing version information from the web and compaares it with.
###	current version.
################################################################################
	
	def update(self) :
		try :
			import urllib
			f = urllib.urlopen("http://www.cnc-club.ru/gcodetools_latest_version", proxies = urllib.getproxies())
			a = f.read()
			for s in a.split("\n") :
				r = re.search(r"Gcodetools\s+latest\s+version\s*=\s*(.*)",s)
				if r : 
					ver = r.group(1).strip()
					if ver != gcodetools_current_version :
						self.error("There is a newer version of Gcodetools you can get it at: \nhttp://www.cnc-club.ru/gcodetools (English version). \nhttp://www.cnc-club.ru/gcodetools_ru (Russian version). ","Warning")					
					else :
						self.error("You are currently using latest stable version of Gcodetools.","Warning")					
					return 
			self.error("Can not check the latest version. You can check it manualy at \nhttp://www.cnc-club.ru/gcodetools (English version). \nhttp://www.cnc-club.ru/gcodetools_ru (Russian version). \nCurrent version is Gcodetools %s"%gcodetools_current_version,"Warning")					
		except :
			self.error("Can not check the latest version. You can check it manualy at \nhttp://www.cnc-club.ru/gcodetools (English version). \nhttp://www.cnc-club.ru/gcodetools_ru (Russian version). \nCurrent version is Gcodetools %s"%gcodetools_current_version,"Warning")					
				


################################################################################
### Graffiti function generates Gcode for graffiti drawer
################################################################################
	def graffiti(self) :
		# Get reference points. 
		
		def get_gcode_coordinates(point,layer):
			gcode = ''	
			pos = []
			for ref_point in self.graffiti_reference_points[layer] :
				c = math.sqrt((point[0]-ref_point[0][0])**2 + (point[1]-ref_point[0][1])**2)
				gcode += " %s %f"%(ref_point[1], c)
				pos += [c]
			return pos, gcode
		
		
		def graffiti_preview_draw_point(x1,y1,color,radius=.5):
			self.graffiti_preview = self.graffiti_preview
			r,g,b,a_ = color
			for x in range(int(x1-1-math.ceil(radius)), int(x1+1+math.ceil(radius)+1)):
				for y in range(int(y1-1-math.ceil(radius)), int(y1+1+math.ceil(radius)+1)):
					if x>=0 and y>=0 and y<len(self.graffiti_preview) and x*4<len(self.graffiti_preview[0]) :
						d = math.sqrt( (x1-x)**2 +(y1-y)**2 )
						a = float(a_)*( max(0,(1-(d-radius))) if d>radius else 1 )/256
						self.graffiti_preview[y][x*4] = int(r*a + (1-a)*self.graffiti_preview[y][x*4])
						self.graffiti_preview[y][x*4+1] = int(g*a + (1-a)*self.graffiti_preview[y][x*4+1])
						self.graffiti_preview[y][x*4+2] = int(g*b + (1-a)*self.graffiti_preview[y][x*4+2])
						self.graffiti_preview[y][x*4+3] = min(255,int(self.graffiti_preview[y][x*4+3]+a*256))

		def graffiti_preview_transform(x,y):
			tr = self.graffiti_preview_transform
			d = max(tr[2]-tr[0]+2,tr[3]-tr[1]+2) 
			return  [(x-tr[0]+1)*self.options.graffiti_preview_size/d, self.options.graffiti_preview_size - (y-tr[1]+1)*self.options.graffiti_preview_size/d]


		def draw_graffiti_segment(layer,start,end,feed,color=(0,255,0,40),emmit=1000):
			# Emit = dots per second
			l = math.sqrt(sum([(start[i]-end[i])**2 for i in range(len(start))]))
			time_ = l/feed
			c1,c2 = self.graffiti_reference_points[layer][0][0],self.graffiti_reference_points[layer][1][0]
			d = math.sqrt( (c1[0]-c2[0])**2 + (c1[1]-c2[1])**2 )
			if d == 0 : raise ValueError, "Error! Reference points should not be the same!"
			for i in range(int(time_*emmit+1)) :
				t = i/(time_*emmit)
				r1,r2 = start[0]*(1-t) + end[0]*t, start[1]*(1-t) + end[1]*t
				a = (r1**2-r2**2+d**2)/(2*d)
				h = math.sqrt(r1**2 - a**2)
				xa = c1[0] + a*(c2[0]-c1[0])/d
				ya = c1[1] + a*(c2[1]-c1[1])/d
			
				x1 = xa + h*(c2[1]-c1[1])/d
				x2 = xa - h*(c2[1]-c1[1])/d
				y1 = ya - h*(c2[0]-c1[0])/d
				y2 = ya + h*(c2[0]-c1[0])/d
				
				x = x1 if y1<y2 else x2
				y = min(y1,y2)			
				x,y = graffiti_preview_transform(x,y)
				graffiti_preview_draw_point(x,y,color)
			
		def create_connector(p1,p2,t1,t2):
			P1,P2 = P(p1), P(p2)
			N1, N2  = P(rotate_ccw(t1)), P(rotate_ccw(t2))
			r = self.options.graffiti_min_radius
			C1,C2 = P1+N1*r, P2+N2*r
			# Get closest possible centers of arcs, also we define that arcs are both ccw or both not. 
			dc, N1, N2, m = (
					(
						(((P2-N1*r) - (P1-N2*r)).l2(),-N1,-N2, 1)
							 if  vectors_ccw(t1,t2) else
						(((P2+N1*r) - (P1+N2*r)).l2(), N1, N2,-1) 
					)
					 if vectors_ccw((P1-C1).to_list(),t1) == vectors_ccw((P2-C2).to_list(),t2) else
					(
						(((P2+N1*r) - (P1-N2*r)).l2(), N1,-N2, 1) 
							 if vectors_ccw(t1,t2) else
						(((P2-N1*r) - (P1+N2*r)).l2(),-N1, N2, 1)
					)	 
				)
			dc = math.sqrt(dc)
			C1,C2 = P1+N1*r, P2+N2*r
			Dc = C2-C1 
			
			if dc == 0 :
				# can be joined by one arc
				return csp_from_arc(p1, p2, C1.to_list(), r, t1)

			cos, sin = Dc.x/dc, Dc.y/dc
			#draw_csp(self.transform_csp([[ [[C1.x-r*sin,C1.y+r*cos]]*3,[[C2.x-r*sin,C2.y+r*cos]]*3 ]],layer,reverse=True), color = "#00ff00;" )
			#draw_pointer(self.transform(C1.to_list(),layer,reverse=True))
			#draw_pointer(self.transform(C2.to_list(),layer,reverse=True))
			
			p1_end = [C1.x-r*sin*m,C1.y+r*cos*m]
			p2_st  = [C2.x-r*sin*m,C2.y+r*cos*m]
			if point_to_point_d2(p1,p1_end)<0.0001 and point_to_point_d2(p2,p2_st)<0.0001 :
				return ([[p1,p1,p1],[p2,p2,p2]])
			
			arc1 = csp_from_arc(p1, p1_end, C1.to_list(), r, t1)
			arc2 = csp_from_arc(p2_st, p2, C2.to_list(), r, [cos,sin])
			return csp_concat_subpaths(arc1,arc2)

		if not self.check_dir() : return
		if self.selected_paths == {} and self.options.auto_select_paths:
			paths=self.paths
			self.error(_("No paths are selected! Trying to work on all available paths."),"warning")
		else :
			paths = self.selected_paths
		self.tool = []
		gcode = """(Header)
(Generated by gcodetools from Inkscape.)
(Using graffiti extension.)
(Header end.)"""
		
		minx,miny,maxx,maxy = float("inf"),float("inf"),float("-inf"),float("-inf") 

		# Get all reference points and path's bounds to make preview

		for layer in self.layers :
			if layer in paths :
				# Set reference points
				if layer not in self.graffiti_reference_points:
					reference_points = None
					for i in range(self.layers.index(layer),-1,-1):
						if self.layers[i] in self.graffiti_reference_points :
							reference_points = self.graffiti_reference_points[self.layers[i]]
							self.graffiti_reference_points[layer] = self.graffiti_reference_points[self.layers[i]]
							break
					if reference_points == None :
					 	self.error('There are no graffiti reference points for layer %s'%layer,"error")
					 	
				# Transform reference points
				for i in range(len(self.graffiti_reference_points[layer])):
					self.graffiti_reference_points[layer][i][0] = self.transform(self.graffiti_reference_points[layer][i][0], layer)
					point = self.graffiti_reference_points[layer][i]
					gcode += "(Reference point %f;%f for %s axis)\n"%(point[0][0],point[0][1],point[1])

				if self.options.graffiti_create_preview :
					for point in self.graffiti_reference_points[layer]:
						minx,miny,maxx,maxy = min(minx,point[0][0]), min(miny,point[0][1]), max(maxx,point[0][0]), max(maxy,point[0][1])
					for path in paths[layer]:
						csp = cubicsuperpath.parsePath(path.get("d"))
						csp = self.apply_transforms(path, csp)
						csp = self.transform_csp(csp, layer)
						bounds = csp_simple_bound(csp)
						minx,miny,maxx,maxy = min(minx,bounds[0]), min(miny,bounds[1]), max(maxx,bounds[2]), max(maxy,bounds[3]) 
						
		if self.options.graffiti_create_preview :
			self.graffiti_preview = list([ [255]*(4*self.options.graffiti_preview_size) for i in range(self.options.graffiti_preview_size)])
			self.graffiti_preview_transform = [minx,miny,maxx,maxy]

		for layer in self.layers :
			if layer in paths :

				r = re.match("\s*\(\s*([0-9\-,.]+)\s*;\s*([0-9\-,.]+)\s*\)\s*",self.options.graffiti_start_pos)
				if r :
					start_point = [float(r.group(1)),float(r.group(2))]
				else :
					start_point = [0.,0.]
				last_sp1 = [[start_point[0],start_point[1]-10] for i in range(3)]	
				last_sp2 = [start_point for i in range(3)]

				self.set_tool(layer)
				self.tool = self.tools[layer][0]
				# Change tool every layer. (Probably layer = color so it'll be 
				# better to change it even if the tool has not been changed)
				gcode += ( "(Change tool to %s)\n" % re.sub("\"'\(\)\\\\"," ",self.tool["name"]) ) + self.tool["tool change gcode"] + "\n"
				
				subpaths = []
				for path in paths[layer]:
					# Rebuild the paths to polyline.
					csp = cubicsuperpath.parsePath(path.get("d"))
					csp = self.apply_transforms(path, csp)
					csp = self.transform_csp(csp, layer)
					subpaths += csp 
				polylines = []
				while len(subpaths)>0:
					i = min( [( point_to_point_d2(last_sp2[1],subpaths[i][0][1]),i) for i in range(len(subpaths))] )[1]
					subpath = subpaths[i][:]
					del subpaths[i]
					polylines += [ 
									['connector', create_connector(
													last_sp2[1],
													subpath[0][1],
													csp_normalized_slope(last_sp1,last_sp2,1.),
													csp_normalized_slope(subpath[0],subpath[1],0.),
									)]
								]
					polyline = []
					spl = None
					
					#  remove zerro length segments
					i = 0
					while i<len(subpath)-1:
						if 	(cspseglength(subpath[i],subpath[i+1])<0.00000001 ) : 
							subpath[i][2] = subpath[i+1][2]
							del subpath[i+1]
						else :
							i += 1
					
					for sp1, sp2 in zip(subpath,subpath[1:]) :
						if spl != None and abs(cross( csp_normalized_slope(spl,sp1,1.),csp_normalized_slope(sp1,sp2,0.) )) > 0.1 : # TODO add coefficient into inx
							# We've got sharp angle at sp1.
							polyline += [sp1]
							polylines += [['draw',polyline[:]]]
							polylines += [ 
											['connector', create_connector(
													sp1[1],
													sp1[1],
													csp_normalized_slope(spl,sp1,1.),
													csp_normalized_slope(sp1,sp2,0.),
											)]
										]
							polyline = []
						# max_segment_length 
						polyline += [ sp1 ]
						print_(polyline)
						print_(sp1)
						
						spl = sp1
					polyline += [ sp2 ]	
					polylines += [ ['draw',polyline[:]] ]

					last_sp1, last_sp2 = sp1,sp2
					
					
				# Add return to start_point
				if polylines == [] : continue
				polylines += [ ["connect1",  [ [polylines[-1][1][-1][1] for i in range(3)],[start_point for i in range(3)] ] ] ]
				
				# Make polilynes from polylines. They are still csp.
				for i in range(len(polylines)) :
					polyline = []
					l = 0
					print_("polylines",polylines)
					print_(polylines[i])
					for sp1,sp2 in zip(polylines[i][1],polylines[i][1][1:]) :
						print_(sp1,sp2)
						l = cspseglength(sp1,sp2)
						if l>0.00000001 : 
							polyline += [sp1[1]]
							parts = int(math.ceil(l/self.options.graffiti_max_seg_length))
							for j in range(1,parts):
								polyline += [csp_at_length(sp1,sp2,float(j)/parts) ]
					if l>0.00000001 :
						polyline += [sp2[1]]
					print_(i)
					polylines[i][1] = polyline
									
				t = 0
				last_state = None
				for polyline_ in polylines:
					polyline = polyline_[1]
					# Draw linearization
					if self.options.graffiti_create_linearization_preview :
						t += 1
						csp = [ [polyline[i],polyline[i],polyline[i]] for i in range(len(polyline))]
						draw_csp(self.transform_csp([csp],layer,reverse=True), color = "#00cc00;" if polyline_[0]=='draw' else "#ff5555;")

	
				# Export polyline to gcode
				# we are making trnsform from XYZA coordinates to R1...Rn
				# where R1...Rn are radius vectors from grafiti reference points
				# to current (x,y) point. Also we need to assign custom feed rate 
				# for each segment. And we'll use only G01 gcode.
					last_real_pos, g = get_gcode_coordinates(polyline[0],layer)
					last_pos = polyline[0]
					if polyline_[0] == "draw" and last_state!="draw":
						gcode += self.tool['gcode before path']+"\n"
					for point in polyline :
						real_pos, g = get_gcode_coordinates(point,layer)
						real_l = sum([(real_pos[i]-last_real_pos[i])**2 for i in range(len(last_real_pos))])
						l = (last_pos[0]-point[0])**2 + (last_pos[1]-point[1])**2 
						if l!=0:
							feed = self.tool['feed']*math.sqrt(real_l/l)
							gcode += "G01 " + g + " F %f\n"%feed
							if self.options.graffiti_create_preview :			
								draw_graffiti_segment(layer,real_pos,last_real_pos,feed,color=(0,0,255,200) if polyline_[0] == "draw" else (255,0,0,200),emmit=self.options.graffiti_preview_emmit)
							last_real_pos = real_pos
							last_pos = point[:]
					if polyline_[0] == "draw" and last_state!="draw" :
						gcode += self.tool['gcode after path']+"\n"
					last_state = polyline_[0]
		self.export_gcode(gcode, no_headers=True, comments=self.tools[layer][0]["comments"])				
		if self.options.graffiti_create_preview :
			try :
				# Draw reference points			
				for layer in self.graffiti_reference_points:
					for point in self.graffiti_reference_points[layer] :
						x, y = graffiti_preview_transform(point[0][0],point[0][1])
						graffiti_preview_draw_point(x,y,(0,255,0,255),radius=5)
			
				import png
				writer = png.Writer(width=self.options.graffiti_preview_size, height=self.options.graffiti_preview_size, size=None, greyscale=False, alpha=True, bitdepth=8, palette=None, transparent=None, background=None, gamma=None, compression=None, interlace=False, bytes_per_sample=None, planes=None, colormap=None, maxval=None, chunk_limit=1048576)
				f = open(self.options.directory+self.options.file+".png", 'wb') 
				writer.write(f,self.graffiti_preview) 
				f.close()
				
			except :	
				self.error("Png module have not been found!","warning")
				

										
################################################################################
###
###		Effect
###
###		Main function of Gcodetools class
###
################################################################################
	def effect(self) :
		start_time = time.time()
		global options
		options = self.options
		options.self = self
		options.doc_root = self.document.getroot()

		# define print_ function 
		global print_
		if self.options.log_create_log :
			try :
				if os.path.isfile(self.options.log_filename) : os.remove(self.options.log_filename)
				f = open(self.options.log_filename,"a")
				f.write("Gcodetools log file.\nStarted at %s.\n%s\n" % (time.strftime("%d.%m.%Y %H:%M:%S"),options.log_filename))
				f.write("%s tab is active.\n" % self.options.active_tab)
				f.close()
			except :
				print_  = lambda *x : None 
		else : print_  = lambda *x : None 
		if self.options.active_tab == '"help"' :
			self.help()
			return
		elif self.options.active_tab == '"about"' :
			self.help()
			return
		
		elif self.options.active_tab ==  '"test"' :
			self.test()
			
		elif self.options.active_tab not in ['"dxfpoints"','"path-to-gcode"', '"area_fill"', '"area"', '"area_artefacts"', '"engraving"', '"orientation"', '"tools_library"', '"lathe"', '"offset"', '"arrangement"', '"update"', '"graffiti"', '"lathe_modify_path"', '"plasma-prepare-path"']:
			self.error(_("Select one of the action tabs - Path to Gcode, Area, Engraving, DXF points, Orientation, Offset, Lathe or Tools library.\n Current active tab id is %s" % self.options.active_tab),"error")
		else:
			# Get all Gcodetools data from the scene.
			self.get_info()
			if self.options.active_tab in ['"dxfpoints"','"path-to-gcode"', '"area_fill"', '"area"', '"area_artefacts"', '"engraving"', '"lathe"', '"graffiti"', '"plasma-prepare-path"']:
				if self.orientation_points == {} :
					self.error(_("Orientation points have not been defined! A default set of orientation points has been automatically added."),"warning")
					self.orientation( self.layers[min(1,len(self.layers)-1)] )		
					self.get_info()
				if self.tools == {} :
					self.error(_("Cutting tool has not been defined! A default tool has been automatically added."),"warning")
					self.options.tools_library_type = "default"
					self.tools_library( self.layers[min(1,len(self.layers)-1)] )
					self.get_info()
			if self.options.active_tab == '"path-to-gcode"': 
				self.path_to_gcode()		
			elif self.options.active_tab == '"area_fill"': 
				self.area_fill()		
			elif self.options.active_tab == '"area"': 
				self.area()		
			elif self.options.active_tab == '"area_artefacts"': 
				self.area_artefacts()		
			elif self.options.active_tab == '"dxfpoints"': 
				self.dxfpoints()		
			elif self.options.active_tab == '"engraving"': 
				self.engraving()		
			elif self.options.active_tab == '"orientation"': 
				self.orientation()		
			elif self.options.active_tab == '"graffiti"': 
				self.graffiti()		
			elif self.options.active_tab == '"tools_library"': 
				if self.options.tools_library_type != "check":
					self.tools_library()
				else :	
					self.check_tools_and_op()
			elif self.options.active_tab == '"lathe"': 
				self.lathe()
			elif self.options.active_tab == '"lathe_modify_path"': 
				self.lathe_modify_path()
			elif self.options.active_tab == '"update"': 
				self.update()
			elif self.options.active_tab == '"offset"': 
				if self.options.offset_just_get_distance :
					for layer in self.selected_paths :
						if len(self.selected_paths[layer]) == 2 :
							csp1, csp2 = cubicsuperpath.parsePath(self.selected_paths[layer][0].get("d")), cubicsuperpath.parsePath(self.selected_paths[layer][1].get("d"))
							dist = csp_to_csp_distance(csp1,csp2)
							print_(dist)
							draw_pointer( list(csp_at_t(csp1[dist[1]][dist[2]-1],csp1[dist[1]][dist[2]],dist[3]))
										+list(csp_at_t(csp2[dist[4]][dist[5]-1],csp2[dist[4]][dist[5]],dist[6])),"red","line", comment = math.sqrt(dist[0]))
					return	
				if self.options.offset_step == 0 : self.options.offset_step = self.options.offset_radius
				if self.options.offset_step*self.options.offset_radius <0 : self.options.offset_step *= -1
				time_ = time.time()
				offsets_count = 0
				for layer in self.selected_paths :
					for path in self.selected_paths[layer] :
										
						offset = self.options.offset_step/2
						while abs(offset) <= abs(self.options.offset_radius) :
							offset_ = csp_offset(cubicsuperpath.parsePath(path.get("d")), offset)				
							offsets_count += 1
							if offset_ != [] : 
								for iii in offset_ :
									draw_csp([iii], color="Green", width=1)		
									#print_(offset_)
							else :
								print_("------------Reached empty offset at radius %s"% offset )
								break
							offset += self.options.offset_step
				print_()
				print_("-----------------------------------------------------------------------------------")				
				print_("-----------------------------------------------------------------------------------")				
				print_("-----------------------------------------------------------------------------------")				
				print_()
				print_("Done in %s"%(time.time()-time_))				
				print_("Total offsets count %s"%offsets_count)				
			elif self.options.active_tab == '"arrangement"': 
				self.arrangement()

			elif self.options.active_tab == '"plasma-prepare-path"': 
				self.plasma_prepare_path()		


		print_("------------------------------------------")
		print_("Done in %f seconds"%(time.time()-start_time))
		print_("End at %s."%time.strftime("%d.%m.%Y %H:%M:%S"))
		
		
#						
gcodetools = Gcodetools()
gcodetools.affect()					

